Communication is important, as stated above.

I have more endurance than DH though he always starts out faster. It takes me forever to warm up. It's important to figure out when one should wait for the other person (what if something happened?) or if the faster person should circle around and meet up. There's a really really fine line between making a ride be a nice social event and accidentally insulting ones spouse by acting like they are riding too slowly.

I guess expectations in advance are good.

As much as I like the idea of a tandem, I think we are both too strong-headed for one. Then again, you never know