Replace leader with a bigger sucker?

I’m doing the French/string trellis method, and one of my guys snuck a sucker past me. It’s now as large as the main leader, and honestly looks a little more vigorous. Can I clip the leader and have the new sucker take its place, or should I clip the sucker and allow the original leader to continue?

(I know that there are varied opinions on pruning to a single leader. I’m not dogmatic about it in general, but I’m using this method this year out of curiosity, so I’m sticking with it.)