Speed control has nothing to do with bridge length, but is solely stroke related.
When a short distance is used between the bridge hand and grip hand, this allows for a different shoulder angle than when a long distance is used between the bridge hand and grip hand.
With a long bridge/grip distance, the bridge arm is extended straighter causing the shoulders hence upper body to rotate toward the bridge hand. You are standing at a angle to the shot.
With a short bridge/grip distance, the shoulders hence upper body does not need to rotate as much and you are standing more square to the shot than with a long bridge/grip distance.
Just my observations about my playing. Recently, I’ve been paying attention to my shoulder angle in relation to the shot. I’ve founded being more square to the shot helps my consistency and a short bridge/grip distance allows for this.
If you use the same pace of stroke with varying bridge lengths, using smooth acceleration generated naturally--and it helps to stroke back to the bridge hand consistently, the bridge hand forming a natural swing fulcrum--the cue stick has more time to accelerate with a longer bridge.
I've showed this to many students and it works every time to help them automate speed control.
What cannot logically work as well is to use, for example, a consistent 11-inch bridge, and on one shot backstroke three inches and on the same shot next time backstroke eight inches, and rely on "feel", aka a jerking motion forward with poor timing and poor cue stick angle.
Yes, pros use super-long bridges and at times, super-short backstrokes, which is a learned technique that requires a grip change mid-stroke to do effectively, but can anyone explain how using the same length bridge while varying backstroke length is more efficient than always stroking back to the fingers? As part proof, I will let students in clinics do their usual thing then make them guess how long or short their backstroke was--they always err.
3-inch bridge: thought is "smooth backstroke to fingers, then smooth forward" = soft stroke
5-inch bridge: thought is "smooth backstroke to fingers, then smooth forward" = soft-medium stroke
7-inch bridge: thought is "smooth backstroke to fingers, then smooth forward" = medium stroke
Less variables in the stroke is a good thing, yes? Guaranteed speed control is a good thing, rather than a lunging stroke, yes?
And Duckie and anyone else, no disrespect, but TRY what I'm saying before telling me further comments that it's "wrong".