Who??? Me???? writes:

How far can you safely trim up the outdrive at low speed on a sterndrive?

I routinely run with the tips of the prop rotating up above the water, such
as when approaching the ramp. You're kind of dog-paddling, and the
steering is unresponsive and unstable (the thrust vector pointing acutely
up in the air), but you can move that way, and it beats dragging the skeg.
On my Mercruiser Alpha unit, that's all the way up in the trailering
position, at the upper limit.