I've had multiple conversations with people, though, granted, it hasn't gotten any specific concrete result yet. But I'm not expecting overnight results.
As the creator of Kismet I'm a user just like everybody else and your experiences echo mine. I did recently release an update to match users with empty profiles only against each other, so that should help. Measuring responsiveness would require me to "get in the middle" of the conversation a la AngelList or CoFoundersLab, which I don't like for privacy reasons.
I compare it to real-life networking events: the majority of people you talk to aren't that interesting or helpful, but you have to talk to them to find out. Kismet just lets you do it without leaving the house :)
I agree with also that you don't need to measure responsiveness.
However, one thought I have is if the user doesn't fill out pros and cons, what good is making the match? They either don't need anything or have nothing to offer. Perhaps match with other users that also put nothing?
You don't have to measure responsiveness. You could create a tip sheet with some best practices to promote better engagement and, I guess, link to it in every email.
Experience is going to vary.