Tried this out on a simple "would you like to book for an event" campaign.

Delighted when I got yes, please book me and invoice me replies right away.

Then the drama. No, that person doesn't work here any more, no I'd didn't click etc.

Turns out their mail software is checking the links in the email and clicks the "Yes" link first. Caused embarrassment, can't be fixed for 5% of all my 200,000 subscribers which leads to an error rate way higher than I can accept. Sadly, useless.