I beg to differ, at least a bit, though I realized that everyone's experience is individual and YMMV.

I have had little or no difficulty redeeming awards on AA and partners for any trip on which I've wanted one. This includes flights (typically F domestic or J overseas) and upgrades to those classes, though it does include one Y award from AA's promo of free systemwide economy tickets after two RTs from the US northeast to Florida and/or California last spring.

The secrets are not rocket science. I often use them on less popular routes (how many people want to go to Tucson? but that's where my aunt's 90th birthday celebration was), I'm flexible about airports (can't get into Miami in January? Well, if I can leave from Miami, can I get into Orlando and use an open-jaw?) and, within reason, dates. If you give the AA folks - not only the EXP desk - reasonable parameters to work with, they can often do good things for you.

Advance notice can help, but I'm not usually in a position to have much. I suspect it's not as essential as one might think since, unless you're first in line on day 1, someone else may have been - especially for those two F seats to HNL on a Friday in early January. More award seats open up over time, as AA's yield management software decides it's sufficiently likely that they'll go unsold, and there's no way to predict when this will happen.