by the looks from the link you supplied, muungwana, it could as well be the composite of what you already said, namely:
application/script similar to pclos repo speed test with built in list of servers, so which ever has the smallest ping, the settings are amended by the application system wide. since its all default access points, link wont break on the next dial in, so the day after once you start the connection, it will most probably work not with the original settings, but the ones applied the previous day, as found by the optimizer software.
btw, maybe it could be possible for the code folks to disect the optimiser for macosx, since that would be easy to translate to linux terms- i know i sorted out my trouble with the 3g umts stick, talking to poor tech guy for an hour, till he gave me ALL the settings, including the modem calls

there is one more thing affecting the sat internet access users:
overcast and bad weather conditions in general, been reported elsewhere and know it from friends experience, took me a while, but proved to be affected really.
btw: the closest physical location not necessarily translates as the fastest one- ping time rules