OK this is completely stupid, but the problem seems to be a setting that's not availabe to set natively in the GS3 it's called "pulse notification". can't find it anywhere. . .but i did find a workaround. . .
if you're not wanting to use lightflow and just want to rely on the GS3 settings to actually work (like me), do this:
install NFC Task Launcher. . . set up a task (doesn't matter if you dont' have any tags), add "display-->notification led" and set it to "disabled"
then manually run this task. . . once you do, the gmail blue led will not flash anymore. . .then go into your settings and turn back on the checks you want
I use Llama to set my turn my led off at night when chargind and back on in the morning. . . but the blue led kept flashing for gmail, this solves this problem. afterwords, you can uninstall NFC task launcher if you wish.