To say vs to have said

[Waji]

Hi, everyone.
Would you tell me what is the difference in meaning between the two sentences?
1: He must not have been in his right mind to have said that.
2: He must not have been in his right mind to say that
Thanks!

 

[Keith Bradford]

There is no difference in meaning, but neither is very colloquial. Prefer 3: He can't have been in his right mind to say that.

 

[Waji]

There is no difference in meaning, but neither is very colloquial. Prefer 3: He can't have been in his right mind to say that.

Thanks sir.
But are the two possible?
I mean, are they natural at all?

 

[Keith Bradford]

They are grammatically correct. But then "My green cat eats hammers" is grammatically correct!
Are they natural? Not very, because they are long-winded - they use more words than necessary. That's not good English.