Very good points KMac. I too allow my 8u 52 his "lumps" with the 55/58 lb boys. I think it helps prepare him for the tuff matches his own wt. Besides, he is pushing the edge of 55 all the time, he could have to move up to them soon anyway.
We have guest wrestlers that come by from time to time from smaller clubs in the area that are looking for a little closer wt competition. We have a little over 100 kids in our club, so we hit alot of wt classes. I don't think your club should get upset if you "visited" a practice once in awhile to help your wrestlers out.
