strength plateu's/"supertraining"

On pg 289 heading “Interaction between diffrent training means”

It talks about some findings on athletes peaking in strength after 3 months or 50-60 training sessions, and if gone ove rthis may impair technical events &/or plateu progress(boxing/javelin). I have seen this in some of my athletes i have coached and myself. is this why CF used a triple periodisation?

if one is experiencing a plateu is it as simple as incorporating a rest week to overcome this?