OK, I see what you are saying, but in reality, it seems to work. I havent heard of any disco's on capture.
If it is hot enough that you are 3.4 on a 3, it is probably NA anyways!
You are basically tricking the box with what it thinks are the altitudes. Due to the heat, it still thinks it is at 3, when it is at 3.4, so the 2.8 should be an issue. We can get a capture pretty far out depending
This is similar to the baro-vnav at extreme cold, coded path is 3.5 to actually have a 3.0.