Is it just me... or does his sideboard plan seem like it would have been a better main-deck choice anyway?

Ignoring for the moment that 4horsemen is essentially a deck built around violating slow play rules, this is a pretty fragile combo, even if he goes off turn 2, a surgical or extirpate can just kill his deck, any other graveyard hate stops it if timed well, anyone who calls a judge over stops him(lol), and the usual control elements (force, pierce, thoughtsieze, etc) get in the way too, plus the artifact hate options like pride mage or shattering spree can stop him.

I mean, sure the painter-stone combo isn't perfect, but it seems a lot more reliable than his main-deck plan, since it isn't grave reliant, in a format where grave hate is basically required thanks to dredge and to a lesser extent reanimator, and Show and Tell emrakul is another pretty good combo already anyway.

If he just played his sideboard combos main deck over the horsemen combo, and had a more generally useful sideboard, I can't help but feel he could have had better odds...