I have confirmed a third fundamental type of walk speedup, I'm going to call it Lurching. To perform it just stand still then walk in a direction. In general, walking accelerations are superimposed with a Lurch. If your VR has a Lurch, besides speeding up it will suddenly become slower when the Lurch period ends. Lurching is almost the reverse of Skating: it applies to the beginning of your walk instead of the end. For most VRs, Lurch speed and duration is equal to the speed and duration of their walking Skate. (Angelan is a clear exception).
There is no way to extend a Lurch, whether by holding crouch or doing it repeatedly. Lurching can be done after any action that leaves you standing still, such as a jump cancel, landing freeze, stationary standing shot, or dash cancel (you must not hold a direction at the last frame of a dash cancel). If you use imaginary walking prior to the Lurch it will be slightly faster than the basic version. Holding crouch or rowing can make Lurches slightly faster. Lurching does not apply when doing walking shots.
Cypher can Lurch in all directions. The effect is brief but enough to be a helpful dodge after a freeze. There's no special input so it's free and can be seamlessly transitioned into anything. It just helps to know that it's there.
Grys-Vok has the best Lurch. It is fast, long, and coupled with a startup walking animation which further deceives the homing of incoming projectiles. I actually described this earlier in the greyed-out post of this thread. Unfortunately since it can't be done after crLTCW he has minimal occasion to use it. It's possible to alternate Lurches and Skates but this isn't any better than repeated Skates.
Specineff has a Lurch but it's a minimal speed increase and not worth remembering.
Lurching exists in Force, and in VOOM influences additional things: you have to walk for the Lurch duration before you can do a sliding crouch attack, and the angling of diagonal dashes is affected as well. Since most VRs do not visibly Lurch the speed boost may be zero and the duration is likely the length of the startup walking animation.
Bal-Bas-Bow has a fast and very long Lurch. (Fortunately there is a trick to doing sliding crouch attacks from a standstill). He mostly air rows because his walking speed is slow, but he has an advanced ground rowing technique. Bal-Bas-Bow can add rowing to the end phase of his dash, then optionally continue the row seamlessly into a Lurch, then dash again and repeat.
Temjin has a Lurch which can be used passively, however dashing with him is way faster and more prevalent.
Belgdor has a negative Lurch; it slows him down and can help make him easier to hit while he is trying to build up his ground rowing, which is ultra fast. This is important because of the "imaginary walking" rule. Rowing speed can be pre-built to maximum, but every time Belgdor starts walking from a standstill he will at least have to contend with a brief negative Lurch.
Raiden has a slight negative Lurch. It's insignificant but explains why he can do a sliding crouch attack before walking to full speed.
Rowing and Skating
Lurching and Skating
I came to a new realization, in VOOT all dash cancels move at lurching speed by default. This holds individually for each direction. That is why dashcancel speed is usually equal to walking speed, as most VOOT VRs have no lurch. In contrast, most Force VRs do lurch in some directions, and dashcancel speeds are usually faster than walking speeds. (It is difficult to notice walking lurches in Force because VRs also have sluggish walking accelerations. To see lurches, one good way is to hold a constant direction at all times while jump canceling repeatedly. In between jump cancels you can see lurch-to-walk speed drops, as walking accelerations are removed via the imaginary walking rule.)
In Force all dash cancels move at lurching speed too, holding individually for each direction, because all lurches and skates are the same speed. Walking acceleration/deceleration, lurches, skates, and dashcancels do not need to have the same duration, though there are many instances where they are the same.
VOOT Angelan is an interesting example because she has drastically different skate and lurch speeds. She has a significant lurch in the forward direction only. She has no lurch in forward-diagonal, sideways, or other directions. That is why her dashcancel speeds are typically equal to her walking speeds, yet she has a fast dashcancelskate by holding crouch, despite having no ordinary crouchwalk. When she presses crouch during a dashcancel, the speed changes to that of her forward lurch.
Since VOOT has the bug where holding crouch changes your speed to that of your forward speed, there is only one dashcancelskate speed (unlike in Force). There is likewise only one walking skate speed, since you need to press crouch to do the technique. But what if you don't hold crouch and just consider the brief speed increase at the instant Angelan stops walking? It seems that a VOOT VR has only one walking skate speed even if you don't hold crouch, equal to its forward lurch speed.
In Force all dash cancels move at lurching speed too, holding individually for each direction, because all lurches and skates are the same speed. Walking acceleration/deceleration, lurches, skates, and dashcancels do not need to have the same duration, though there are many instances where they are the same.
VOOT Angelan is an interesting example because she has drastically different skate and lurch speeds. She has a significant lurch in the forward direction only. She has no lurch in forward-diagonal, sideways, or other directions. That is why her dashcancel speeds are typically equal to her walking speeds, yet she has a fast dashcancelskate by holding crouch, despite having no ordinary crouchwalk. When she presses crouch during a dashcancel, the speed changes to that of her forward lurch.
Since VOOT has the bug where holding crouch changes your speed to that of your forward speed, there is only one dashcancelskate speed (unlike in Force). There is likewise only one walking skate speed, since you need to press crouch to do the technique. But what if you don't hold crouch and just consider the brief speed increase at the instant Angelan stops walking? It seems that a VOOT VR has only one walking skate speed even if you don't hold crouch, equal to its forward lurch speed.
Boosting
With the new ability to study frame data, I confirmed the phenomena of lurching exists in general for all VRs and directions. In most cases the speed difference of the lurch is not clearly noticeable, but it is rarely zero. I confirmed that the speed of lurching in a given walking direction is always equal to the speed of dash canceling in the same direction. Walking skates are equal to the speed of dash cancel skates, minus a frame of deceleration.
My (not yet published) frame and speed data also reminded me of a phenomena I had forgotten. It is a simplification to state that holding crouch changes your walking speed to the forward walking speed. More precisely, holding crouch mirrors your back directions to your forward directions for walking, crouching, and skating. Back walking speed becomes the forward walking speed, but side and diagonal walking speeds can be slightly different (usually still similar to the forward walking speed). The side and diagonal multipliers for fastwalking appear to be global on a VR.
Speed data revealed a fourth fundamental type of walk speedup which I will call Boosting. To use it just keep walking in the same direction for a very long time. If you keep walking a VR will keep accelerating very slowly forever. This is likely a glitch. The amount of acceleration leak varies by direction and VR, but to give a typical example, after walking across a whole stage your walking speed could be comparable to dashing speed. Boosting can be done invisibly but the moment you let go of the direction you will rapidly lose all your boost. Boosting can stack with fastwalking, dash cancels, and 'new' rowing as long as it is performed first.
My (not yet published) frame and speed data also reminded me of a phenomena I had forgotten. It is a simplification to state that holding crouch changes your walking speed to the forward walking speed. More precisely, holding crouch mirrors your back directions to your forward directions for walking, crouching, and skating. Back walking speed becomes the forward walking speed, but side and diagonal walking speeds can be slightly different (usually still similar to the forward walking speed). The side and diagonal multipliers for fastwalking appear to be global on a VR.
Speed data revealed a fourth fundamental type of walk speedup which I will call Boosting. To use it just keep walking in the same direction for a very long time. If you keep walking a VR will keep accelerating very slowly forever. This is likely a glitch. The amount of acceleration leak varies by direction and VR, but to give a typical example, after walking across a whole stage your walking speed could be comparable to dashing speed. Boosting can be done invisibly but the moment you let go of the direction you will rapidly lose all your boost. Boosting can stack with fastwalking, dash cancels, and 'new' rowing as long as it is performed first.