ad hominem leanings

Anyone who is seriously interested in a topic recognizes the mistake of an "ad hominem" argument.

"Ad hominem" (Latin: "to the man/person") arguments critique the person espousing a position and by extension dismisses the position involved. Briefly, an asshole making an argument is making an asshole argument. As Wikipedia puts it, ad hominem argument "means responding to arguments by attacking a person's character, rather than addressing the content of their arguments."

In serious discussion, ad hominem arguments are generally frowned upon as both fallacious and idiotic, however common. Deriding a (wo)man is hardly a reason to deride or dismiss the position that (wo)man advances.

In serious discussion, such a technique is frowned upon.

I wonder, in light of this approach, why it is that thinking highly of a (wo)man should not excite a similar displeasure when hearing his/her arguments. Whether the person involved is a sage or an idiot ... either way, ad hominem thinking can only infrequently be involved in assessing the issue at hand. And yet such skepticism is sometimes given a 'bye' when listening to someone who is admired or lauded.

If the Dalai Lama says so, well ... maybe I like the Dalai Lama. If Karl Rove makes an argument, well ... maybe I dislike Karl Rove. Is my skepticism and critical-thinking capacity bruised by my personal leanings? I imagine it well might be.

What then happens to the issue at hand?