That sounds like a theoretical question... Will a larger SGA make recovery faster for a generally small database that requires very little recovery, not likely. But if the database is larger either in the 100's of GB or terabyte range, doesn't it still depend on the type of recovery needed and how that recovery makes use of the SGA.
I would bet that someone could create a large 10g test database with a 2GB SGA with auto tuning features turned on and a known amount of recovery that needs to happen. Perhaps you can do 10 large updates on different sqlplus sessions, then without commiting in any session, do a shutdown abort and bring up the database with timing turned on. Then change the SGA to 4GB and do the exact same test again.
I would guess that if the SGA is properly sized making it gigantic would not help, and some would argue that if you make the SGA too large it might take longer to recover. But enough speculation let us know how it turns out!
this space intentionally left blank