Michael

" ..... I said both most and I believe. These are sufficient qualifications - in my opinion - to make the reply one of merit and not an ad hominem attack. "

Most people who criticise, most people who drink coffee, most people who ride motorcycles, most Americans who travel overseas,.....

Certainly, use of the words 'most + group name' disqualifies the commentary as being directed at one person in particular, but it does stereotype, does it not?

Which is the lesser of 2 evils; ad hominem attacks or stereotyping?

"I believe". I don't agree with your opinion that use of these words disqualifies a remark as being an ad hominem attack.

For example, I believe that Joe Blow is the ugliest man who ever walked the surface of Earth, I believe she is an idiot, etc. Ad hominen, or not?

Using both "most" & "I believe" in the one remark doesn't, in my view, make any difference.

Cheers