I'm...not actually sure. I suppose I...could make it with less caffeine, but I don't think I'd be able to do that without my knowledge that decaf tastes different influencing the outcome.

[Also, the idea seems to physically pain him.]

It's not a problem for me, at least, for...complicated reasons that ultimately boil down to my not having to worry about certain adverse effects anymore, but it is true that too much of it would affect everyone else's health. Granted, by the time anyone's gone past simply being a bit jittery, we'd probably be just plain tired and want to go back anyway.