In a competitive game I would say that this is not only good, but actually required. For D&D it is simply extra baggage that some enjoy using and others don't.
Terms like "back up" "proof" "challenged" are all indicative of competetive play whether against fellow players (to avoid being outshined), the DM (to survive the harsh realm of rules-lawyerism) or both.
Yes, exactly yes. For some this is the reality of gaming. While my preference is that it be a cooperative experience, this may not be the preference or experience of others.
Tyrlaan, what is your quibble? What is the significance of "house rules"? Why are they "sometimes not valid", and who is the judge? If I call myself "Thaumaturgist Games" or something and put out a book with the OGL in the back, does that make my rules more valid? Does it make them any better?
If you want to play that sub-game of the build, then of course you need the apparatus for it. If you want to get into number-crunching as your mode of play, then you need to know the numbers.
It doesn't have jack to do with the "individuality" of characters. That's not how we "play our roles" in real life!
Ari, I think you're taking my comments further than their intent. See further EW's comment I've quoted above and my reply. If the above is not the way your game plays, than I'm probably not splitting any hairs about how your game functions.
To address some of your house rule questions:
Firstly the judge, IMO, should be the GM
and the players. MY take on gaming is that the GM and the players are cooperating to have a good time. It's an unspoken social contract of sorts. As a result, everyone at the game table should understand and agree with house rules.
Secondly, some people are either not good at, don't have the time to, or dislike for some reason building house rules and would prefer to rely on something with that "official" feel, a.k.a. in a rulebook somewhere.
On your last point, I disagree. It can do exactly what house rules do for individuality. Note I state can, since obviously not all complex rules actually produce anything productive.
I could argue that we do play our roles this way in real life. I'm a project manager. I put that on my resume. It has significant impact on how my chances are to get a new job. It can be "challenged" reasonably by someone calling my previous employer. On the other hand, if I merely stated I was a project manager because the world lacked jobs (oh the joy to dream!) and I just wanted to be one, how do I support it?
But all of that said, it's a silly line of arguing anyway, since we're not really talking about modeling real life in the first place.