Like 12-String Mike, I too was wondering about drop-down tuning (and also, w/capo). It's something I used to do regularly (with and w/o a capo) until I switched to using s&s strings. When using brass-wound, it's a must for me in order to get better tuning/tone/action.
After many years, I found I was having to tune down again when I bought a Yama APX500 (a nice little kick around guitar) last Spring. I didn't want to waste a new set of brass wounds...so I haven't put a set of s&s's on yet.
Unlike jj's cool/dry I had an issue with heat/humidity all summer, which has continued off and on. There's no A/C for my upper level here and I hadn't played the guitar all summer. I hadn't tuned down the strings and had left the capo on. I was upset with myself for neglecting it when I finally got around to picking it up and had 2-3 strings buzzing
.
I had an issue with a single buzzing string that I wasn't able to resolve on the Ibanez I traded in for the Yama so I was thinking "not again"
. It was another few weeks until I had a chance to deal with the buzzing strings on the Yama. Thought the neck seemed a little off just eye-balling it, but it checked out fine with a line level. Anyway, in no time I found that the pegs for these strings had popped slightly so that was an easy fix.
I did have a problem finding proper-fitting pegs for the Ibanez which was probably the issue that I had with the buzzing on that single string.
Back on track w/this thread, I also wondered if Gordon may have to tune down to compensate for any issue related to the environment affecting his guitar, string action or even acoustics, etc.