It was a Hogan era trend to keep the trail elbow close to the side. With the success of Nicklaus a new trend to let the elbow move away was introduced. Very few tour pros today keep their trail elbow near ala Hogan; most are like you see in the Trahan video.
As I've posted quite often, for the vast majority of ams I've seen if they let their trail elbow get away from their sides it does not get back to where it needs to be (in front of the trail hip) with the proper position (bent nearly 90 deg at elbow and wrist) so the shot is compromised.
Not to distract you too much from your current pursuit, but if you feel that a steep swing is easier on your back there is another swing that was designed to be optimal and the proponents are all 'regular' people - the Blake Swing
. Richard Wax says on video that there should be no more stress on your body or effort than it would take for you to turn at the dinner table and speak to someone next to you. You can examine the video
for yourself at the Blake forum but I can tell you that impact is excellent and during Blake's time such regular golfers as Ed Sullivan adopted the swing.