In/out play in coupler

Boduke said

Safety pin in the coupler. Dowel pin.. not the pin holding coupler to the splines on the box. A coupler with 2 pins ceases to be a coupler, no?

Click to expand...

No. The large pin that holds the shoes in place only holds the shoes in place. The tiny pin only keeps the coupler from falling off. Neither one restricts the action of the coupler itself. You're thinking to hard about it.