Yeah, that was meant as a response to Shale. If he'd voted Corwin, town would have won! Could we then say town demonstrated good play this game? Heck no, cause being crazy like this game certainly wouldn't result in town winning consistently. Town got incredibly lucky with the paranoid cop hitting one scum N1 and then another scum withdrawing. That only leaves one scum, meaning town's got at least a 25-33% chance to win by pure chance.
What are some things that are good play? Looking for connections between people. The only difference between scum and town, by definition, is that scum know who their friends and enemies are. Obviously they try to hide this but due to human psychology and the necessity of advancing the scum agenda it usually comes out anyway. Scum also have an agenda, they have certain people besides themselves that they do not want to see get lynched. All other things being equal, a scum will be for lynching townies and against lynching fellow scum. Obviously again they'll try to act contrary to this at times to disguise themselves, but they can't carry that too far because townies outnumber them and losing any of their number has a pretty drastic impact on their chances of winning, all other things being equal. Usually there are power roles in the town who can do various things that hinder the scum agenda, scum want to find out who these people are and kill them, while town wants them to do their thing in peace.
Beyond that, like any game, you move into metagaming, figuring out what strategies on each side are popular in a given situation and working from there. For example, in the earlygame when there's not much information around, scum most often tend towards attacking townies and not each other. Usually they'll only flip around to attacking their buddies if they're making an active, planned move to mislead the town, potentially trading off one of their members in the process. In this game, Tom attacked Excal day 1 and 2, not knowing that Keeshi would come out of nowhere and make him die and flip scum. Because of that it was most likely that Tom's actions were promoting the default scum agenda of "lynch townies, not buddies" and Excal was most likely town. Note all the usuallys and most likelys. Nothing is ever guaranteed, but certain things are more or less likely.