Got it. The tricky thing seems to be that sensitivity to stakes is an obvious virtue in some circumstances; and (intuitively) a mistake in others. Not clear to me what marks that difference, though. Note also that maximising expected utility allows for decisions to be dictated by low-credence/likelihood states/events. That’s normally intuitively fine, but sometimes leads to ‘unfairness’ — e.g. St. Petersburg Paradox and Pascal’s wager / mugging.
I’m not entirely sure what you’re getting at re the envelopes, but that’s probably me missing something obvious. To make the analogy clearer: swap out monetary payouts with morally relevant outcomes, such that holding A at the end of the game causes outcome O1 and holding B causes O2. Suppose you’re uncertain between T1 and T2. T1 says O1 is morally bad but O2 is permissible, and vice-versa. Instead of paying to switch, you can choose to do something which is slightly wrong on both T1 and T2, but wrong enough that doing it >10 times is worse than O1 and O2 on both theories. Again, it looks like the sortition model is virtually guaranteed to recommend taking a course of action which is far worse than sticking to either envelope on either T1 or T2 — by constantly switching and causing a large number of minor wrongs.
But agreed that we should be uncertain about the best approach to moral uncertainty!