I can actually see the hat thing being counter-productive.
- "Do you want to wear a hat?"
- "Why should I wear a hat?"
If you anticipate it will be a problem, and you're shooting 1 person at a time, I'd shoot a tight close-up of the face cropped at the forehead or hairline (if the thinning is more evident on top than in the front). It probably violates one of the "rules", but nuts to that :) I find the most interesting feature of many older people are their eyes anyway.
If you shave them completely they will be hip
"What's grandma up to?"
"Just hangin', like she always does."
I have nothing constructive to contribute except something I overheard in the markets a few weeks ago when I was out for lunch with my girlfriend. We walked past two elderly women speaking near a fruit stall and caught just a snippet of their conversation,
"Yes, but that's because bald men look like penises"
I know I shouldn't, but I really want to know the context of that conversation...
From a 21 year old with a conveniently shaven head (I'm not losing my hair, of course not...)