If you mean function well like, do decent? Eh, monk's not too hard to do decently. None of the jobs in this game are hard to do "decently" at. Really just push the buttons that make sense, hit positionals if ya got 'em, and never not be doing something and you'll do well on anything. You can perform within 80-85% of a job's potential just by looking at your tooltips, figuring out a combo that kinda makes sense, and remembering to always be doing something.

Squeezing the last drop of DPS out of a job? Well that's a whole 'nother side of things.