So… I’ve played a bunch, here actually, and have some thoughts.
Among an experienced group stabbing Merlin is a viable evil strategy. It can be hard to be an effective Merlin, and not get pegged. There is certainly a lot of misdirection. An interesting challenge.
Our experience is that Merlin takes the knife maybe 1/3 games that good wins. Perhaps as high as 50%. But that’s also because the way that things shift when you have records of votes, and can look over statements for ‘tells’. So probably half of evil wins come from stabbing Merlin.
Roughly 1/3 evil wins outright
1/4-1/3 good wins but Merlin gets shanked
Remainder good wins and Merlin gets away.
But we have a fairly developed and sophisticated PBF meta, and certain player personalities. And perhaps my perception of stabbinga is skewed because I tend to be the one taking the knife! Even when I’m not Merlin there’s like a 50% chance I get stabbed at the end, or so it seems.