Tut, tut BL!! Don’t presume, now. Me, I failed Mindreading 101. 
I think that listening to the dancers steps (and watching them, for instance, to see that they rise on the 2-3, 5-6 of a jig and land on the 1 and 4) is important.
But it will only get you so far: there is a lot of rhythmic variation rolled into the melody lines, I think, and the better players are the ones who use ornamentation and variation for rhythmic expression: things like how long you hold the first note of a long roll, and so forth. Then there is the different rhythmic characters of the different reels and even parts of reels. Think Congress Reel vs. Wise Maid or Humours of Lissadell vs. Star of Munster, and so forth. So I think if a drummer wants to know what rhythm to play, he should learn to play/lilt/hum the tune. (I don’t regard this as hardship, btw. After all, everybody else learns the tune, too, or sits it out.)
Reminds me of an exchange I once overheard while playing around the fringes of a big session:
“Gee, maybe I should try that drum thingy, I don’t think I could learn an instrument”
[my emphasis]
I remember seeing a documentary on tv about tap dancing in Harlem in the early 1920s. The dancers were all quite adamant that all the fancy jazz drumming that would come later in the 30s and 40s was based on the rhythms the tap dancers were inventing. Wonder if ITM percussion couldn’t take a hint from this.
djm