My monk PC stayed back & peppered him with crossbow bolts...Monks need to use different tactics and have different strengths.
Well, this might just come back to what the late, lamented Hong said about Monks - "Whatever it is that they do it, it doesnt seem to be what most people want them to do."
I didnt take any bow feats because I didnt think of a Monk as a crossbow archer. (If it had been a short bow, I might have felt a little more positive about it. Maybe thats just me.)
And, sure, plinking away with the crossbow is going to be a more effective tactic than getting your face punched in by a Giant, but basically your contribution to the fight is a d8+0 of damage every two rounds (assuming you dont ever miss!) Your party is going to have to be very understanding in order to consider this "contributing". Tactics like this are why other party members start looking at the Monk and asking "Why are you even here? "
You would presumably admit that monks are good at not dying, due to great saves, movement, immunities, evasion abilities, etc?
But they are good at dying because of low HPs. ;-) This is the crux of the arguement that Monks cant stand toe-to-toe with big monsters. Which is to say "When the fight gets tough, the Monk...runs away and pulls out a crossbow?"
I've gone negative my fair share of times; basically if you are scouting, you are vulnerable to being surprised by a power oriented monster. A power monster usually only needs two rounds to kill a Monk so - bang - "DM: You are surprised, no DEX, he hits you twice. Take 28. Roll Init. He wins, he goes first, you are still flatfooted. One hit, take 19. Your turn, what do you do? Oh, you are dead already? Oh. OK. Well then....um."
And this isnt even considering the case where you tactically have to stand and fight. If there are three Trolls and only two real Fighters, the party expects the Monk to step up and occupy the third Troll.
Again, it comes back to expectations - the Monk might not be particularly suited for a toe-to-toe fighting role, but since he isnt particularly suited for anything else, the rest of the party will expect him to contribute in whatever way he can best. And in this case, thats stepping up and sucking up two rounds of punishment from a creature that he has absolutely no chance against.