I'd like to put a slightly new spin on this thread. If we adopt the idea of "practice makes perfect" and allow a player to roleplay a concept/class/whatever that is slightly beyond his/her current capabilities, how can the rest of the group and the DM help that person to get "perfect practice" so that he/she actually improves?
I'll give you an example: A friend of mine likes to play swashbuckling heroes, like the main character in almost any Errol Flynn movie, and he generally does it well. In our current campaign, however, he's decided to play a swashbuckling fighter/cleric. The swashbuckling part goes rather well, but sometimes I wish he would pay more attention to his choice of spells and how he uses them during combat. He doesn't seem to read the spell descriptions beforehand and his knowledge of what spells are available seems to be a wee bit narrow. His character has memorized spells that didn't work the way he wanted them to, he has forgotten to cast "cure spells" on badly damaged characters in combat (our DM dislikes OOC-advice during combat, so we can't tell him 'my character needs healing ASAP'. We're allowed to say things like "Meadred looks badly damaged, and won't hold up much longer". Talking hit points left is a no-no. ) and so on. I would like to get him to focus on how to utilize his character's potential better, but I'm unsure of how to do it in a manner that will let him continue enjoying the game.
So, what is your advice?
Cheers,
Meadred
Edit: Clarification of OOC-statement.