The recruits, still in civilian clothing, are marched away. But they carry out a somewhat complex drill maneuver. Initially, they were in two rows as they faced the Sergeant, the General, Uncle Jim, and Joan. They are ordered to march away to their right and in a way that they go from two rows into four columns. Raw recruits would NOT have been able to carry out such a maneuver as they would have been ignorant of both the command and movement, unless, of course, they had been instructed how by the director, take after take.
When the rat is gunned down in between the doors, there is a slight delay from when the bullets punch through the glass in the door to when the victim reacts from the bullets hitting him. The victim should be reacting immediately the moment the glass is pierced by the bullets.
At the start of the film there are two gangsters burgling a jewelry store. One turns on a flashlight and the other chastises him for turning on the flashlight and then swats at it. But as he is chewing him out, the flashlight stays lit for about 4 seconds. A truly professional criminal would known better to have left that light on for those 4 seconds. A truly profession criminal would have swatted at the light first to get it out as quickly as possible, then, and only then, would he have reamed the torch bearer out.
When the recruits are in line being looked over by the Sergeant, a General arrives and talks to Frank (who is line next to Louis). Louis then interrupts and says to the General "Hey Doc, gotta match?" The General gives Louis a dirty look BUT complies by lighting his cigarette. To ask a General for a match and to address him as such would NEVER have been tolerated. INSTEAD the Sergeant would have shouted at Louis to shut up and NEVER address an officer, particularly a General, without first being addressed himself. He would then have gone on report and would have ended up digging latrines or peeling potatoes for the next month. HOWEVER this infraction was just the beginning. Frank then introduces his uncle (who was there accompanying the General) to Louis and the General retreats into the background while Louis and Uncle Jim exchange pleasantries. Again, this sort of thing would NEVER have been tolerated by either the General or the Sergeant. Shouting would have ensued, Louis compelled back into line. BUT then this outrageous scene gets even worse. The General comes back to the forefront as Frank introduces Louis to his sister (who was there accompanying her uncle). Louis then says to the General "Pardon me Doc" puts his hand on the General's arm and brushes him aside. The General gives a stunned look at Louis, BUT says or does NOTHING. This whole situation would and could NEVER have happened. And it would NEVER have been allowed progress to the point that this recruit would have put his hand on a flag officer. Any and all such infractions would have been dealt with then and there, least anyone else present take on such airs.