If we played good football chances are we would be winning. What's peculiar about Scottish football? It's one of the worst leagues in Europe and like any other league, the lower teams tend to raise their game against the better ones. I don't think there's anything special about it whatsoever. As said, if Scottish teams were so difficult to beat playing proper football, they would be proving so in Europe - instead of getting annihilated every single season.
The only time we've played good football in recent memory is Warburton's first season where we blew everyone away, until the last few games.