Shows how teams compared rushing from single-back to multi-back sets. TT would not be considered a RB, but when we motioned Eddie Royal into the backfield for our triple-option runs (which I remember a lot of), that would count as a 2 RB run. So my guess is this shows the relative ineffectiveness of those triple-option types of plays compared to our regular spread option single back runs, and also indicates Larsen was not a great runblocker compared to our 2+TE sets or multi-WR formations (which I think we all acknowledged... he was better in pass pro).