Air is mostly nitrogen anyway (78% by mass). It won't help much as most leaks are broken seals between tire and rim which will let even the biggest molecules out.
Exactly. I don't see it being anything more than a hassle. Besides, everything is affected by temperature, especially
I'd rather have cement tires and rubber roads (no flat tires and no road buckles)...it's just as ridiculous, but certainly more advantageous.