Originally Posted by
JonNYC
It most definitely can. Don't do it.
Or, do it, but then don't come back complaining if you get caught.
Or, do it, and then after the missed flight, tell AA (at prefunds.aa.com) "hey, you know the unflown segment sitting out there in open status where the flight was delayed (or where the flight had a sched change or where the flight had an equip change or or or) - will you refund it?"
and when you get the refund back for the value of the segment (calculated roughly based upon distance) on your credit card in a few days, sleep comfortably that it was all done it plain sight, open and notorious