We pushed Yamaha very, very hard about putting 3 or 4 F350 engines on both the Deep Impact and the Hydra-Sports new 41. Both boats can handle the weight and would fit many of our customers (we are one of the largest Yamaha package dealers in the world).
The word from corporate is that it was never designed as a high speed (read go-fast) style outboard. It was designed for big heavy slow cruisers that were slated for diesel power. That is the reason for the non high speed gearcase, limited prop selection, and no provision for quad controls. They have zero interest right now.
We fight with them weekly so keep your fingers crossed.
I think it might be cool to have twin exhausts, above water, coming from each motor!! They were not as entertained and mentioned something about millions invested to make them quiet.