Rare Pair Shorts

*nods* I understand what you're saying. This is a percentage problem that cuts both ways. If we look at the proportion of one pairing to ALL pairings then there will be too many that are rare. If we DON'T include all pairings then there will be too few that are rare (IMO, of course). No matter what, it throws uncertainty on the straddling-the-fence pairings in the middle. By one comparison, it could be rare and by another, not.

Honestly, I think that if a pairing represents less than 2-3% of all het fics, then it's rare...even if it ends up being 7-10% of all unpopular-pairing het fics. For instance, I think Snape/Luna is rare. But there's an exchange for it and a bit of fic here and there. I think you would consider it not rare. Then again, I have a higher threshold for rarity. It comes down to definitions and cutoffs, I guess.