It appears I have fixed my problem where the LED light was staying stolid instead of blinking for notifications. I went into the Advanced settings in the Notifications section and I enabled/disabled the Always Pulse, Succession, and Pulse in Order settings. I did this a few times, and I also tested the flash for each of my notifications. Lo and behold, my LED lights now blink for notifications. I can't remember the exact order that I changed these settings, but I do currently have them all OFF, and both my Gmail and SMS notifcations are working properly. It's worth a shot for anyone else having this problem.
I tried what you listed here, and it seems to work.
In fact, I noticed that after doing the enable/disable for those advanced settings when I do a "test LED" under an app (google voice / gmail) the lights blink during the test.
A test email sent also shows that my LED's blink (they stayed solid before).
So for me at least, what you posted works!