I do try to add something to the description, at least. Anecdote: I had an almost-nemesis when I worked at the Hermiston Herald. The commander of the chemical weapons depot next to Hermiston for part of my time there didn't like me. He also didn't like the media in general: no lie, he once wrote an essay that, in my opinion, boiled down to The media should always just trust the military and report what we say, because why would we lie to you? I'm a Navy brat who appreciates our armed forces and I still know that he was being unfair. It dawned on me later, long after I'd stopped dealing with him, who he reminded me of. Describing him to Mike Russell when we had a long chat after my first Can't Stop the Serenity screening, I referred to this commander as "J.T. Walsh without the charm." Mike winced. And it was scary-accurate, both in how this commander looked and how he acted.
Another time I watched the worthwhile fantasy miniseries The 10th Kingdom, and summed up Scott Cohen, who played Wolf, with a similar reference. Handsome guy (I also didn't recognize that he'd also played the scumbag Denby on NYPD Blue), with a deep well of nervous energy, what from being a werewolf and all. I looked at Cohen as Wolf and thought He looks like a cross between Alec Baldwin and Adam Sandler.
But here's one time I overdid this. I'm glad my Herald editor Michael Kane edited out one such reference. I'd profiled a local guy, not much older than me, and who had a voice uncannily like that of Tom Skerritt from Picket Fences and Top Gun. In the draft I turned in to Michael, I mentioned this and said "It's a voice you can trust." He cut that, and after thinking about it, I understood why: Why did him sounding like a recognizable actor mean you could trust him? And it was a distraction in the article. It wasn't about him, one of the subjects of the profile. He wasn't Cary-Grant-except-his-ears-were-larger. Not at all.
I realized I started doing that more lately. A former co-worker became, in my mind, "a female, squished John Noble from Fringe." For one example. I came up with another one yesterday that I won't repeat. Because it's not the best habit and I should stop thinking in terms like that. (I shouldn't have thought that about Mrs. Not-John-Noble, either, but I have reasons to be uncharitable towards her.) I'm tempted to ask people So do you want me to say who you remind me of?, but, again, breakin' the habit is a good thing. So never mind.
Unless it's scary-accurate.