Day before weigh-ins allow some guys to get down a little further than they would in season. With the next world team weight being 163 and filled with kids that wrestled 160-170 in season, 145.5 was the best/only option to wrestle at a world weight for Retherford. Weighing in at 145.5 now would not be indicative of being undersized for a weight class 3.5 lbs heavier 6 months from now.Well Zain just competed at 145 at the Freestyle Junior Nationals losing to Pico in the finals. It would seem that he would be pretty undersized at 149 6 months from now. Zain's a good-sized 141 (not huge, but perfect frame for the weight, he'd look small next to the top 149 lbers) Zain would certainly be the pre season #1 at 141 with Steebler, Mitchell Port and Devin Carter graduating. The highest returning all American is Dean Heil, who was mediocre until the national tournament. I think Zain would be a heavy favorite to win at 141. 149 on the other hand has some returning studs in Tsirtsis, Sorensen and Clagon. Also Richardson from Old Dominion and Neff from Lock Haven are returning all Americans as well. Assuming Hunter Steiber is healthy, he's at least a strong AA candidate and I'm not buying the rumor that he's cutting down to 141.
My 2 cents
Also Retherford has never been much of a weight cutter so I wouldn't be surprised if he wrestled 149 even if he is undersized. That being said I agree with you that he looks to have a better shot at 141 than 149.