As YR said, most MPP cams have an installed centerline 2 degrees smaller than the LSA. However that is not a one size fits all. It's a one size fits most. BUT..here is the problem...most guys that are paying 500$ for half a day on a dyno aren't going to change the cam timing and do more pulls because it's a pita with most setups, but you are likely leaving performance on the table by not doing so. Sometimes you can guess and hit a sweet spot if you have pror experience and make that decision based on the whole combo. I.e. run a single plane intake and advance the CL a little more .
NOw..to answer your question.. Does 2 degrees of ignition timing make a difference in performance? Rhetorical, and that's just spark. Imagine advancing the entire valvetrain movement.