Interesting question Finley!
It seems to me that the pilot,, with some experience, automatically adjusts the nose up trim to compensate.
For example if the hypothetical 9a with a 320 and a fp Catto uses 65 kts indicated airspeed for their final approach then an equivalent 9a, but with a 360 and a Catto (pitched for the greater hp) might require a slightly higher angle of attack to maintain the same final approach speed which results in similar landing performance. The 9a airframe/wing likes a particular approach speed and the pilot cancels out the extra residual thrust from the bigger engine/prop with up trim to get to that magic number.
I have experienced relatively long landing distances on my 360/9a due to too high an idle setting and due to too high an approach speed. However, as Larry mentions, the 9 can also drop out from under you, similar to a 6 or a 7 (don't ask how I know) if you let the speed bleed off too much. With a constant speed prop the deceleration is quicker and therefore the potential drop out could occur even faster to a distracted pilot.
RV9a/ECiIO360/James Cowl/WW RV200 Prop
Flying since 3/06 and still smiling!!!