I mention both those issues in the new 101.
Carryover (my experience before I knew of Kafka) is that a rapid rise in temp in a hot oven means it's rising faster, thus more carryover.
The issue about the gray outside is one we have discussed and is good to know. Me, it's not that big a deal, I've never heard anyone mention it at all, until we started talking in the forum.
I like my method. Start low, rest, finish high. Works for me