Wonder if this is as true for bikes as it is for cars and motorcycles? After all, whereas in a car (at least for cars with an engine in the front!) most of the weight is in the front (60% or more) and suspensions tend to "dive" with hard braking, bikes aren't like that. The other thing is that I've been taught over the years to bias toward the rear, to avoid flipping over the bars on hard breaking. Indeed, my spouse didn't once, and paid the price...
I guess I just don't see any way to transfer weight forward, unless one is going down a very steep hill!