Davan, more often than not, when you make an abrupt change in a training program eg. inclusion of OL’s in favour of simpler lifts like squats/deads etc, there is a period of lowered CNS stress, where the athlete gets better at OL’s by improving his intermuscular coordination (a learnt skill), and precisely because of the lower CNS stress, gains can manifest themselves elsewhere – in other H.I training elements.. It’s kinda like a mini-taper
I am talking about long term improvements after stagnation. I am not talking about a temporary benefit, but people who had previously not been improving and have been improving significantly since. They are most definitely proficient in the lifts.