To my knowledge and understanding the Denver stretch offense utilized the concept of stretching the defense laterally to open holes or seams along the front. Stepping off at a 45 degree angle the line. The C, G, T, and TE, playside could move the defense laterally while the backside G and T or C , G, and T cut blocked to open the cut back lanes. Hence the Denver Step could be nothing more than the initial 45 degree step and continuation. Denver just made it look easy!! LOL
Shanny had a different Idea about the OL position he went against the norm of finding behemoths to simply over power you. Rather he used smaller faster linemen to simply out quick and get under you. Recall not that long ago when Green Bay went to the Stretch Running game ala Denver. The first year or two was very iffy at best as the power guys they had on the LOS were not adept at getting off and in front of the call side defenders and were very poor at the backside cuts for the same reason. I can still remember seeing the backside OT on several occasions executing what I call the fall at their feet blocks simply because they weren't agile enough to get off in front for the cut.
Indy does almost the same thing except thy like to Pin the EMOLOS and pull around him. Their OL is also small and agile by comparison.