In Oblivion, armor decreased spell effectiveness: http://www.uesp.net/wiki/Oblivion:Magic_Overview#Using_Armor
Presumably mages absorb magicka through their skin. Cloth doesn't inhibit this significantly, but denser materials do. At least that's how I think of it.
I'm not really talking about the effects so much as I am talking about the reasoning behind the effects. What actually causes mages to need to wear robes? If the only point is looking different, isn't that kind of, well, stupid? Why sacrifice protection for the sake of "looking like a mage"?
but the idea of mages existing at all does make sense to you? in all wizard mythology robes are warn as a sign of status.
I'm admittedly not a fan of doing everything regarding fantasy and mythology to the book. Some notions, like every piece of fantasy having humans, elves, dwarves, dragons, etc. need to die, in my opinion of course.
Well, Imperial Battlemages in Oblivion wore heavy armor + a head cowl or whatever you call it, guess you're right about "Mages don't need robes, they can wear armor as well". But mages do NEED to look different, to have a look of their own. Some prefer to wear basic robes that could be bought for 10 gold a pair, some others want to look more 'apparent' and stand out of the crowd with badass armor saying "I am a powerful mage" all over it. It's a matter of preference really. Personally I would like for Skyrim to have an option for both. Options are never ever a bad thing.
I guess in some ways that's what I'm trying to get at. Why to they NEED to look different? Heck, everyone and their mother can use magic in TES. Just because they're a more powerful user of magic shouldn't necessarily mean "I should wear robes!". I will agree on the matter of preference and that options are never a bad thing, I just want to know why people automatically associate mages with staves and robes, or why they continue to feel the need that mages should be associated with staves and robes.
It's not really a question for TES in specific, but more for fantasy in general. Thank you for the responses!