Jim Lehrer has a few words in response to those who thought he let President Obama and Mitt Romney ramble on and roll over him in Wednesday’s presidential debate:

“So what?”

The veteran PBS newsman, who was persuaded by the Presidential Debate Commission to moderate his 12th debate — the last one he’ll do, he vows — says the event wasn’t about “control” or the strict enforcement of rules. It was about producing a sharp discussion and substantive contrast between the candidates. Besides, he says, few people seemed to understand that the new format, which divided the discussion into 15 minute segments, was supposed to encourage such exchanges.

In this edited transcript of a phone conversation Friday morning, Lehrer, 78, lays out his thoughts about what went down in Denver the other night.

Question: What was your overall impression of the debate?

Answer: Well, there was a new format, [that has] never been tried before. People have always said what we really ought to have is a more open exchange among the candidates, keep moderators out of it and let the candidates really talk to each other. Well, this was a step toward doing that. And I felt that from that point of view it certainly worked.

Q: Were there drawbacks to it?

A: I had wanted to cover a lot more ground in terms of subjects. But it took longer because the candidates gave longer answers than I, in an ideal world, would have hoped. And so a lot of things went by the board because of that. But all of the discussion, it seemed to me, was about things that mattered. They weren’t talking about things off in the margins. They were talking about things that truly divide them. I was anxious to try to draw the distinctions and the choices and the differences. Sometimes I was successful, sometimes I was not. But generally speaking, I thought that worked.

Q: People could see that they talked over you and went past the time limits that you were trying to enforce. What was your reaction as that was happening?

A: It was frustrating as it began happening, when they didn’t answer the questions directly and they went over time. But I kept reminding myself: “Hey, wait a minute. Waaait a minute. This isn’t about rules. This is about the reality of the exchange of the two candidates.” So I just backed off. . . . I had no problem doing that. Yes, there were times when I pushed them, and sometimes they ran over and ignored me and all that sort of stuff. So what? I mean, it isn’t about my power, my control or whatever. It was about what the candidates were doing, what they were talking about and what impression they were leaving with the voters. That’s what this is about. It’s not about how I felt about things.

There were several minutes in the middle of the debate where I just backed off and they just talked. And I thought those were the magic moments.

Q: You’ve done 11 debates before this one, but this one seems to have drawn more commentary. How do you view that?

A: All the debates are very different. All the previous ones that I’ve been involved in were very controlled, by nature. The rules were such — two-minute answers, 90-second responses — it was very easy to control that sort of thing. With this one, where you had 15 minutes of open discussion, and there was no formal way to say to Candidate A, “Hey, you’re over the time.” There was no time limit internally within the discussion. So it was up to me, or the good judgment of the candidate, just not to go on and on. Sometimes I was successful at it, sometimes I was not. Sometimes the candidates were successful at controlling themselves, and sometimes not. But that is just the nature of this [format]. A lot of people said it was a good thing to try it. And I agree. So the criticism of me, it’s understandable. Everybody is used to the old way of doing things — where the moderator controls things. So I understand why people were a little startled and criticized me, but they were criticizing me under a set of old rules, not the new ones. [Laughs.]

Q: Do you think we should use this new format again?

A: Absolutely. It probably needs some tweaking. Tweaking not only by the people who put the debates on, but by the candidates as well.

Remember, whatever people are declaring about this debate, who won and who lost, they’re not talking about it the way they talked in the past. They’re not talking about gaffes or some little incident of some kind. They’re talking about what was said. Which is what it ought to be.

Q: Do you have any advice for the next moderator?

A: No! I don’t have any specific advice. The importance of these debates has been demonstrated. The [forthcoming] debates are going to be even more important because this one drew so much attention.

Q: Is this your last time moderating? Will you be back?

A: [Laughs.] You know, if I do another debate, I would first have to chuck my wife and my three daughters and my six grandchildren. No, I agreed to do this this one solely because the debate commission had come up with this new format and they wanted me to give it a try. If this becomes the model for future debates, there will be no other reason for me to moderate another debate.

Q: One last thing: What was your reaction when Governor Romney said he intended to end funding for PBS? Did it sound to you like he was saying, “I’ll take the rug right out from under you if I’m president?”

A: He’s said that before. That didn’t bother me or surprise me.