Yes. Just like with clinchers, tolerances vary. I don't know if the Tufos you have were hand sewn, but adding humans into the construction process probably increases variability. Sitting in my basement I have an orange tubular I was given by Ken Freeman about a year ago. It's brand new, but he was never able to get it on a rim. (I'm not home so can't look up exactly what it is.) I've not been able to stretch it over a rim either. I suspect it's a lost cause (or actually a smaller tubular which was mislabeled?)

If you've not yet applied glue, maybe return them and buy something else or exchange for a new set.