I have flown SSI to PBI.
ATC will try to get you to fly offshore if you file the shoreline route.
With each frequency change, I was given an amended clearance which I
declined. The comments section of my flight plan contained the notice
"NO OVERWATER ROUTING ACCEPTED, NO FLOATATION GEAR ON BOARD".
ATC does not get this information from FSS unless they request it.
ATC personel are not pilots and do not understand that light GA aircraft
cannot glide from offshore routes to the beach.
Do not accept an offshore amended clearance.