When Hawkeye and Potter are talking about fishing, neither is wearing sterile gloves. They both touch their surgical garb, which is filthy. They get up, tie their masks back on, re-enter the O.R, presumably to start operating again. They should have left the room through the exit door to their right to re-scrub.
Potter and Hawkeye are talking fishing. Hawkeye says he hooked a 30lb Sockeye Salmon but it got away. First, there are no Sockeye in the St.Croix river. Second, Sockeye only get to a size of 60 to 84 centimeters in length and weigh from 2.3 to 7 kg.
How does Hawkeye know the salmon weighed 30 pounds if the fish got away before he could weigh it? Any good fisherman knows what a fish will weigh by not only looking at it, but the amount of fight it puts up. On top of which, all fishermen like to tell a good story and embellishing comes of second nature.
In the aid station, when Hawkeye tries to get his hand into the chest of a wounded soldier, you can clearly see his arm is pressed against the soldier's chest and his hand comes back up into the shot for a couple seconds.
When Col. Potter sits down with Hawkeye outside the OR the shadow of the boom mike is visible on the wall in the upper right corner.
Hawkeye leaves Charles his bathrobe, and adds, "purple is the color of royalty." Hawkeye's bathrobe is red, not purple.
B.J. realizes Hawkeye is still alive when he comes across a patient with vertical mattress stitches using white cotton sutures. This is a little baffling as a positive id. Vertical mattress stitching is the most common type of all stitches and white cotton was generally used when nothing else was available: pretty likely at a shelled Battalion Aid station.