Aging is a good thing for older deer for sure, but for younger farm land deer it is not necessary, but doesn’t hurt as long as you keep the meat at a safe temp. Usually the time it takes to get it processed while kept in the cool air or in a fridge if it is warm out is plenty sufficient for young deer. I routinely shoot 1 1/2 and 2 1/2 year olds, skin, quarter, and pack them into the fridge within hours in early bow season. I usually wait about 12 hours before I start cutting and packaging. I then usually finish them within about 24 hr. At that point I put them in the freezer and they are great. If I get a big buck or old doe I quarter and pack them into the fridge and let them set for three or four days. Rigor mortis is the probably the main culprit if your young buck was tough. You need the let the rigger come out before you freeze or eat it. I don’t think cutting is a problem, but I know cooking it while the muscle is in rigor will result in tough meat. If I recall rigor is kind of like a muscle cramp or tightly packed muscle condition. It may also have a chemical component, but I can’t remember. I have also heard that if you freeze the meat before the rigor comes out you can get the same result.
More ammo! I need to shoot something!