You say this, but then say you agree with Alder. Maybe you should title this writing by idiots.

When you check both boxes, you are saying that you are deviating both legs. When you check the box for the first leg, you are saying that you are only deviating on that leg and intend to take the scheduled second leg. Before this contract, there was only one box to check. If it doesn't matter how many boxes you check, why did they add a second box?

I'll say again, Alder may be right. And I'll say again, why not just check the appropriate boxes. I've called CRS when connecting to the second leg and things went bad. I've never been told I was deviating, maybe because I only check the box that says I am deviating on the first leg.