Things that are easy for some members of HN crowd are likely not that easy for a 19yo person who's only notable achievement in life so far is being really good at chess (well, presumably). Such software also doesn't explain his OTB results, which are consistent with his online results.
Some OTB tournaments allow players to go to the bathroom with their phone, others allow audience in same room - so an accomplice (such as Hans' coach Maxim Dlugy - another admitted cheat) could relay moves via signal. I've seen suggestion on Hiraku's channel that current scanning for players for communication devices is sub-par, although Hans has offered to play naked to disprove that theory (some porno site is calling his bluff by offering him $1M to actually do it). Anal beads? I dunno ...
Magnus has estimated it would usually only take one or two computer corrections per game for himself to play perfectly, so we're not talking about every move, just at key points. Apparently even just an indication that there is some key/winning move at a given point, without indicating what it is, is enough for the player to stop and put in the time to find it.
