Abstract
The purpose of this paper is to draw attention to the importance of the backward reaction π+ppρ+ as a test of the wrong-signature nonsense Regge dip mechanism. If the observed dip in backward π+ppπ+ is due to a wrong-signature nonsense zero, then a dip is also predicted to occur in π+ppρ+. This prediction does not involve any arbitrary assumptions about fixed poles, exchange degeneracies, or absorptive Regge cuts.