How much do you know about many worlds, anyways?

Vladimir_Nesov!2009 knew more than enough about Many Worlds to know how to exclude it as a consideration. Vladimir_Nesov!2013 probably hasn't forgotten.

My alternate self very much does exist, the technical term is possibility-cloud which will eventually diverge noticeably but which for now is just barely distinguishable from me.

No. It doesn't exist. Not all uncertainty represents knowledge about quantum events which will have significant macroscopic relevance. Some represents mere ignorance. This ignorance can be about events that are close to deterministic--that means the 'alternate selves' have negligible measure and even less decision theoretic relevance. Other uncertainty represents logical uncertainty. That is, where the alternate selves don't even exist in the trivial irrelevant sense. It was just that the participant didn't know that "2+2=4" yet.