Your basic reasoning is sound. The question comes down to if you believe VWUSX will outperform VTSAX over some reasonably long period of time.
If yes, then stay the course. If no, then do something different.
The general advice to buy VTSAX and forget it is great advice for this very reason. You don't have to wonder and you don't second guess. You just own the market with the belief the overall market will prevail over time.