this is actually a good explanation of why "muscle confusion" is not a useful idea. Efficiency is not the problem. We want to lift with efficiency. The resistance that makes us stronger doesnt come from lifting with inefficient mechanics. It comes from increasing the weight on the bar.
If inefficiency were useful then it would be useful to create unnecessary moment arms in the lifts.
Eric's friend is most likely getting stronger in spite of his programming rather than because of his lack of a program. It would be interesting if Eric could get a hold of his friends log for a month.