Originally Posted by Kurald Galain
I think it does: good game design is to ensure that characters aren't utterly reliant on their equipment; not to decry any and all DMs that use equipment loss as a plot device.
That depends on what you are going for. In different game systems equiptment is of different importance. In shadowrun, for example, I'll buy lots of disposable equiptment, and if a gun gets too hot, I'll toss it. In Dungeons and Dragons, however, that +2 keen longsword
or +3 dancing shield
are important parts of my character(this is more true with 3e and 4e than other editions, but magic equiptment has always been an important part of D&D).
In one game, your equipment are just tools, something you use to get the job done, and they can be replaced. In the other game equiptment can't just be replaced. Even in a high magic setting the party can't just buy a new dancing shield every time one of theirs gets stolen or broken, money is a limited resource and that's not the kind of thing you can find on most store shelves.
In D&D, taking away equiptment from the player for an extended length of time is almost always a bad idea, especially if it is equiptment the character bought or crafted(as opposed to found). Magical items make a character more powerful, and many characters effectiveness is based around the gear they had. Taking away the gear makes the character weaker, and fosters bad blood between the player and the DM. I do think the best way to deal with an overpowered piece of equiptment(or a spell), is to explain the problem to the players, and give them something in return. If they are a good player, and it's not something you pull too often, there shouldn't be a problem.
I don't know why Zeful went off on some wild tangent about "Gentleman's Agreements". A D&D game is not the DM telling a story and the players acting in it, a D&D game is a group storytelling game where the PC's are the main characters. While it is true that the DM is the final arbitrator of the rules, they are not some kind of game god. Everyone, DM and player, should have a roll in the construction of the campaign and story, and a DM should never use their magical rule 0 power to put the players into line.