I mean, Psychotic is right: Lynch All Liars is an established policy. I personally don't like policy lynches, because by their very definition they are inflexible, and I like to consider everything to their proper context.
I agree with Psychotic: it was damn risky, and Mitsuru came under some heat which could've crippled the Town. Despite that, it did work out, it forced Koromaru to claim (making him the number one target), which resulted in Ken having to claim a significantly weaker position (making him face off against Mitsuru, and we know how that ended up)
I'll also go into slightly more detail about why I'm more sympathetic to the risky gambit, but I'll wait until after the game's finished. I will say though Junpei: risky as smurf, but good job.
EDIT: It's easy to be objective. I mean, objectively, yeah, I totally agree with Psy. But subjectively, I can't help but say Junpei's risky gambit was the turning point of the game.
A game which isn't over just yet, though. Day Five could go one of two ways, still.