For some reason I can't find the post you quoted. In any case, I don't believe that Lenamon has ever said, or implied, he'd have used not guilty by reason of insanity.
Here are some things Lenamon has said in regards to Casey Anthony:
http://transcripts.cnn.com/TRANSCRIPTS/0812/08/ng.01.html
Lenamon = Terry Lenamon, Casey Anthony's former death penalty qualified attorney
Grace = Nancy Grace
GRACE: Are you trying to say she`s insane?
LENAMON:
Absolutely not insane. Insanity is not an issue in this case.
and this:
http://transcripts.cnn.com/TRANSCRIPTS/0905/14/ijvm.01.html
Lenamon = Terry Lenamon, Casey Anthony's former death penalty qualified attorney
VELEZ-MITCHELL = Jane Velez-Mitchell
VELEZ-MITCHELL: You appeared on "NANCY GRACE" earlier and said that you had a disagreement with Jose Baez, Casey`s current defense attorney, over strategy that was mental health related. Some people took this to mean well, maybe you were thinking, oh, she should ask for -- she should plead not guilty by reason of insanity. But you`re saying that`s not the case.
What exactly did you mean? What kind of disagreement did you have that was mental health related with Jose Baez?
LENAMON:
It was clearly not -- insanity was not the issue. Miss Anthony has never admitted to this. And she still maintains her innocence.
I was brought in initially to deal with the issue of the death penalty.
When you`re dealing with the death penalty, one of the things you deal with is mitigation, a life history, things that happened to her in her past, things that happened during a period of time where, as you described and some of the panel has described, her behavior was quite questionable.
VELEZ-MITCHELL: So what you`re saying -- just to translate, you`re saying that when you talked about mental health issues, you`re essentially saying, "Hey, if she`s convicted, we should try to point out that she had some mental health issues as a mitigating factor so they don`t give her the death penalty?"
LENAMON: Well, I think, that`s part of it. Part of it is that everyone jumps to the conclusion that just because she`s acting a certain way or a person acts a certain way that they believe that`s consistent with guilt.
It`s not necessarily always consistent with guilt. It may be consistent with some other form of behavior that can be explained. I`m not sitting here on national television saying one way or the other. I was involved in a very limited way in this case. Mr. Baez obtained me to get the death penalty waived. I got it waived.
Four months after they found the body, they decided to seek the death penalty again. And I have concerns now that whoever comes in on this is going to look at it with fresh eyes and not be predisposed to any other theories that the defense may have because when we`re talking about death, we`re talking about the real thing, where this woman may ultimately be executed. And we need someone who is really familiar with this to come in and do the job that needs to be done.
=======================
Sorry if I'm O/T, but I think there is sometimes misunderstanding of Lenamon's stance on this case, and I wanted to record here what he's actually said.