Something I do tend to change, however, I will usually lean to sticking with the trap bar for younger players as it is safer and easier to manage a heavy load, without worrying about the technical side. When you have players deadlifting with low reps it gets competitive and sometime their form can breakdown in the quest to outlift their team mates.
With players who have a high training history and no previous prbolems with their lower back, I am fine with them using a normal Olympic bar and would in fact encourage its use.
In short I am looking for the safest/easiest way to put load through their legs/glutes without compromising their lower back.
Hope this answers your question.
Tom.