Those new-age (back in the day) green machines began to gain traction in the early ’90s, even though they were slow and heavy. Those liabilities were the antithesis to outboard engineering to that date, and though their heavy four-stroke valve train was cleaner, boats couldn’t carry it gracefully on their transom. Evolution kicked in. Boat owners began to see the benefits of them, and boatbuilders began to build boats with wider, deeper transoms to carry them. By the time four-strokes left two-strokes in their wake, motor-makers had trimmed their weight back to the svelte numbers previously achievable only by two-strokes. As a result, most boats today have the better seakeeping abilities of wider, deeper transoms.