As the OP of the "out serve" thread, I am eternally grateful that most, if not all, of my opponents allow us to play a let when there is any confusion/uncertainty of that nature.
I might have said, "You know I think the serve might have been long, but I didn't call it, my partner played it, and your partner played the return. What do you think we should do about it now?" In most cases, when stated that way, your opponents would be hard-pressed to ask for a let, but if they do, I'd let 'em have at least a second serve in the interest of good sportsmanship and harmony. When my out serve was returned at my feet as I was going into my service motion for 2nd serve, my opponent was good enough to offer a let. Just because you don't have to doesn't mean you shouldn't.