Well an explosion is just "a rapid increase in volume and release of energy in an extreme manner". It doesn't necessarily have to involve combustion, but I get what you're saying. Thats the way I read it too, that they were saying because nitrogen (N2, i need sub script damnit) is inert there won't be an explosion from combustion. But I suspect what they meant is that it wont degrade the side walls and cause a catestrophic failure (explosion). This is usually caused by other factors anyway such as low tyre pressure, manufacturing errors etc.
Tyres CAN explode though combusion under VERY rare circumstances though, such as after contacting powerlines.
10psi increase means the starting (cold) tyre pressure is probably incorrect. In circuit racing we look for around a 4psi pressure increase, then we know our tyre pressures are in the ballpark. Its not like nitrogen doesn't expand with heat as well.
Probaby the biggest factor in the extra expansion rate using air is the water vapour. To me that is the ONLY advantage of nitrogen over air, that it is DRY. Because the water vapour levels from different air sources will vary the expansion rates will vary too. If you spent the effort drying air out I see no reason why it wouldn't perform very similarly given that air is 78% nitrogen. Its far easier just to use compressed nitrogen cylinders though. Even so, if you are using a fairly dry air source (say a compressor with a refrigerator dryer) I see absolutely no benifit in road cars using nitrogen. I can understand race teams wanting a super dry gas for race tyres because it helps remove another variable when tuning the car. But you'd have to be right up there in terms of pushing to the extreme. I can't think of any of the club racers I know that use nitrogen.
Hehe yea, but it made for an awesome debate ;)