Well, not to be argumentative, but just as there are losses at wing tips, so must there be losses at blade tips.

A three bladed prop has three tips where draggy vortices are generated, just like a biplane has four wing tips generating vortices. So there's a theory.

But in practice, it seems any good prop is about 85% efficient and there isn't a great deal of room for improvement. People get convinced one brand, or type, whatever, is better than another, but it's really because the prop load happened to match the engine and airframe better than the one they think is inferior.

So I think as a practical matter, if you want to fly with a three bladed prop, the thing to do is get two or three and experiment with which one does best with your plane and your engines.

Jim