Antonio Conte squeezes his players to the max, but tries to get the best out of them in the shortest possible time. Last year he had the advantage of only playing Serie A and Coppa Italia, we will see how all his players will cope this year with their European commitments too.
Rudi Garcia only did damage to Napoli and it was irreversible damage, in fact they finished ninth in the standings that season
I am pretty sure that we are not going to see this change all that much, it's going to be pretty similar to what we already have and not going to be a big deal for Napoli. Sure, having some more games will make them more tired, but I doubt they can do much at UCL, so they will not care about that too much.
What we need to reach right now is the fact that we need to do a better job of it, and if they keep being similarly good at the league, without caring about the rest, then we are not going to end up with any issues. Of course this is tough, and of course it takes time for any place to get better, but that doesn't mean we are going to see them change their approach to league. I have 100% trust in them to realize what is winnable and focus on that.
Obviously Napoli will use all their strength for the Championship, Antonio Conte is also known for having always done badly in the Champions League both with Juventus and Inter and most likely he will do it with Napoli too! Obviously these are my guesses, but it is highly probable that it will happen.Only time will tell if I was right or wrong.