yankel berel: Proclaiming to Klal Yisrael by force of a full-fledged Prophesy that RMMS has arrived to irrevocably take klal yisrael out of galut is an as clear as possible claim to the messiahship.
It’s certainly a clear claim to messianship, but how does that make it the start of the process? The Rambam makes no mention of the aspirer making a claim to be Mashiach. In fact when he talks about Ben Koziba he says that it was Rabi Akiva who declared that BK was Mashiach. (The Raavad, on the other hand, does say that BK himself made the claim.)
A claim which has to verified thru results and reality.
If there is a second coming and a second chance , then there is NO VERFICATION at all.
100%. But there is a negative form of verification, that is that the dead person has done nothing so far to justify the claim that he is Mashiach, and he is therefore no better in this matter than any one of the millions of righteous Yidden who have perished over the last millennia.