Misleading NCAA Tourney grouping

I saw a twitter post, that listed: UVA, Zaga, Duke, Mich St, UNC, Mich, UK, Houston

as the teams with top 20 offense and defense efficiency. Since 2002, the National Champion has had a member of this group all, but once.

The misleading thing is a great run in the tourney improves your efficiency ranks significantly. In fact, teams that won it all have only been top 20 offense/defense efficiency heading into the tourney about half the time.