But unless I'm missing something (which wouldn't surprise me, as you came up with many of the ideas of that thread in the first place), the conservative estimate doesn't obviously hold. A big problem is that Graverobber/Rogue is used in the solution in that thread.
You are right, I missed that. I would estimate that 50 should be possible nevertheless, I think it is more difficult to insert the necessary drawing.
Here's a way to go to 43x (not even using Procession but ignoring the drawing problem)
TR chain + KC chain for 20x triple and 8x double action = 38x each of (G/R and Amb)
that's 14 cards of each action played (using BoM as Amb), 5x left
=> total 43x
PS:
Ok, I figured out how to go above 50x using Procession:
chain of Pro+KC send 10xKC to trash using 4xProcession giving 17x triple plays
then recovering all KC I can get another 20x triple plays
The disadvantage is, that I need 10x G/R to recover the KC from trash, so I need to send some G/R to trash using Procession to play them more often
idea: KC-Pro-G/Rx3 trashes 3xG/R and recovers 6 Cards -> net gain + 3 Cards
In the end, I think this will be limited by the availability of the Amb, so that I can play the chain "only" 57x times.
Perhaps this could be further improved by sending Amb to trash and recovering them, but I'm to lazy to work out the details.