Whats the LED in anyways that your trying to monitor, theres probably a better signal you could get somewhere else with less uncertainty.
Believe it or not, I want to monitor the number of flashes of the LED over a period of time. It "cycles" as a rudimentary way of identifying faults in that system. So "three flashes, break, three flashes, break..." will mean something different than "nine flashes, break, nine flashes, break..."
As that device is a "closed system" and I can't define additional outputs from it to me, I have to work with what I can get.