The ratings take into account the stress level of the players which is different among divisions depending on the tier of the event. That's why you'll see a lower SSA in some leagues for the same layout that was played in an A or B-tier a month later. That's not a problem but a strength in the system that it automatically accounts for increasing pressure on players in higher tiers. Note that a 20-point difference is still less than 5% variance in the ratings. We are more impressed when a player nails a 30-footer for the win at an NT than in a rec round or league night. This differences in pressure changes the challenge of the exact same course in similar weather which is shown when the SSA is calculated. So "yes" you might get a better rating in a higher tier event on courses you know if the pressure doesn't get to you.
Rater of the Tossed Arc