Chip, I noted on your page, good one by the way, you very nicely made a
reference to Section 508. I realize the way you worded it, it is quite
accurate and certainly worth mentioning.
But in the case with the code you provide, which sets timer event at 1
second intervals, you would not be in violation of Section 508.
"j) Pages shall be designed to avoid causing the screen to flicker with a
frequency greater than 2 Hz and lower than 55 Hz."
First - they say screen rather than cell or page or element, but I agree
with your interpretation - the intent is with regard to any element on the
display, not necessarily the entire screen.
They don't want to see blinky things blinking at rates of from 2 through 55
times per second. And viewed that way, 1 second intervals (1 Hz) is entirely
outside of their warning range.