Just a couple of points here:
Terminals for <100A devices can be presumed to be rated at 60C, unless marked otherwise. Many (most??) circuit breakers are marked for 75C conductors. Most 'wire nuts' are marked for even higher temperature. I don't recall any temperature markings on receptacles and the like, however.
Table 310.15(b)(6) can only be applied in a very restricted class of situations. It can only be used with particular wire types and a particular application: the _main_ feed to a residence (including the NEC controlled part of the service entrance), _or_ the feeder supplying the main load of a residence, _or_ downstream feeders in a residence if they are as large as the main feeder. If you do a demand calculation on a residence, and it just happens to come out to 100A, then you can select a 100A conductor from table 310.15(b)(6).
For any load other than those specified in 310.15(b)(6), you have to start with table 310.16 (or the other ampacity tables) for your calculations, even if you are in a residence.
-Jon
