HP is a numbers game for small engines, as they share engine size with different HP ratings. So if he had chosen a 2-stroke model, he would have had to either get a 2.5hp at much lower weight, or a 4hp at the same weight.

Gene did not get a heavy engine, and could not have gotten a lighter 2-stroke without going down in size.

Your Tohatsu is the same engine as Larry's Nissan below. And it is an anomaly, as it is really a 6hp engine with a different carb.

The common knowledge that 2-strokes are lighter than 4-strokes is simply no longer true. I suspect it will take many decades for that meme to go away.

Mark