I play union as a hooker/prop. What not to do is half ass your lifting during the season OR try to keep training with 4 lifting days, 2 club practices, conditioning, and saturday matches. With the former I became weak, with the latter I became overtrained and lost 15 pounds in 2 months.
The best results I've had are also with Joe Defranco's west side for skinny bastards in-season template. You can change the exercises around to make sure you hit the essentials like get-it-done suggests.
It's really important to know your own recovery and make sure to eat and sleep enough if you don't want to be a quivvering injured mess by the end of the season.
Play hard. Cheers!