It depends.
I would expect each coach to spend at least 5 minutes a week making roster adjustments to assure he fields a complete starting line up each week, but that aside it's up to you. Some folks go berserk scouring waiver wires, reading every FF blog, and subscribing to online FF info sites in an effort to win, but that's up to you. I probably spend an hour or two a week on it, but lots of that is just because I'm a huge NFL fan. Plus I like winning these things and you have to field your best players and matchups, or so you think.
But 5 minutes a week (or less) to set a full starting lineup would be the minimum expected. I do get peeved with coaches who don't check in and field empty spots because they haven't benched a player who's on a BYE week.:nono::gigglemad:twak:
PM me if you want in and I'll open it up again.