Scribble
First Post
"All abilities are magic, and magic is available to all" is so far from the implied reality of pre-4e D&D that some of those playing 4e D&D seem to have a very hard time accepting that this is the implied reality 4e is using.
RC
Your trying to use circular logic here that is incorrect.
It's not magic (unless you want it to be) so your statment is incorrect. You can explain it through mundane means (unless you've decided you don't want to, or you lack imagination.)
The option is available to anyone if they want to try it, but the DM will probably make it harder. IE they'll have to make a check of some type.
Having CaGI as a power just gives that player a bonus, in that he doesn't have the harsh penalties. (Akin to taking a feat to make sure you can't be hit by an AoO when you try the special ability.)