For me the key tool for making lose tenons is my little lunchbox planer. I get the thickness dialed in and I have good sticks of tenon material. I check after the first piece so I don't waste all the pieces by making them too thin. I table saw width then round edges on the router table. Takes less time than driving to the store to buy some. If I had to hand plane them or depend on cutting to exact thickness on the table saw I'd probably buy them.