Bounding and multi jump type exercises are very valuable in developing speed and power. It’s key purpose is too develops elastic/ reactive power and enhances the central nervous system which is key for top end speed and ground contact power…It also develops rhythm, postural control and various mechanical issues…
Do not get too caught up in contact times…remember tapping your foot multiple times will not develop any kind of power but is shorter in ground contact than sprinting…
And yes, bounding should be a part of the season the entire year. Emphasis should switch throughout the year from static to running bounds, various more complex sets, with resistance to just body weight, up hill to flat ground, long to short etc etc etc…