All this proves to my mind is that there is as much in the feeding as the breeding.About 25/30 years ago i remember dad keeping a handful of suffolk x mules ram lambs to use as tup lambs on next years mule ewe lambs. Looked upon as so backward now, but he was a top stockman, i kept 2 char x mule ram lambs for teasers, last minute left them entire. Used 2 charmoise, 1 expensive beltex x char, these 2 cross breds, and 3char ram lambs and one older one, fed, on 600 mule ewe lambs. Sold as store lambs at exeter, talked about on price tracker, nett x bred tups paid best, then charmoise, then other 5 the same. E u grade lambs do still return profit regardless what people say, but selling stores out of ewe lambs a useless x bred tup averaged heavier lambs than pure tups and basically were a 65 pound asset and sold 5 months later at 131 it seems an easy system? Add to the fact easiest lambing ever