Adult men over age 35 (+/- 5 years) with perfect heads of uniform density hair are suspect. The eye wants to know more.

- Does the shape of the hairline have a normal irregularity (forgive the oxymoron)?
- Is the hairline receding at the temples in the expected formation? Do these areas of recession (there should be some even for men with the most enviable heads of hair) blend well into the temple?
- Does the density of the hairline change along its course? Typically it does.
- Is there a visible part? Does it lead to a natural-looking cowlick?

Perhaps someone can better formalize what I'm laboring to describe, but if I were a game show contestant on "Guess Who's Wearing?" looking at actual heads, not photos with unreliable or flattering lighting, I would walk away a wealthy man. But, I'm not saying that every good hairpiece sticks out like a sore thumb. Most people are oblivious or simply don't care. Mine is a skill that's been honed over many years of hairline gazing.

I want to also add that I think there's anything wrong with wearing a great-looking hairpiece and having people know about it. Mid-'80s Paul Simon comes to mind. I've not inspected close-up pictures of the piece he was wearing back then, but despite whatever flaws it may have had, I thought it brought a great improvement to his appearance. He couldn't have assumed that people didn't know something miraculous grew on his head (he was losing his hair quickly during the '70s) but frankly I don't remember the public really talking about his new hair at all. His talents were such that they dominated the discussion about him, not his topper.

Same goes for Neil Diamond -- as long as I'm on a thread about iconic pop singers. I think most people know he's wearing a piece, but it becomes him and so, who cares?