When I had mine coming on too early it would start to cut fuel at very low throttle cruise conditions where I didn't want decel. Very annoying.

Barometric pressure is just what is says and there is a pid that you can log for it. Mine seems to stay at 98.54 most of the time. It doesn't move much but I have seen it go to 98.18 and 99.28.

Here is the scanner config file I am using.