The only way to conclusively prove otherwise would be to somehow get the bird in hand, measure the tail and rectrices and examine the 2nd rectrix for emarginations as was done with the two birds caught in 1988. In an effort to test the comparability of my measurements with this key, I carefully measured all birds captured using vernier calipers to the nearest tenth of a millimeter. I also collected 1st, 2nd and 5th rectrices from the right side of the tail of all birds caught. Comparison of standard deviations show that my measurements are as consistent as his. The most probable explanation comes from the fact that Stiles made measurements for his key from study skins and all of my measurements were on living spec imens.
Study skins tend to shrink up some.
He measured rectrix width on the bird. I measured rectrix width on plucked feathers flattened out on a card. What this suggests to me is that, if my measurements tend to be larger, than the anomalous male and female I captured in 1988 would not fit well into Stiles' key without adjusting for the difference between measuring techniques. This adjustment would tend to support their identification as a male and female Allen's Hummingbirds. I would stress here that I am not suggesting the that the data presented by Dr. Stiles is any less correct than my own.