The shed hairs in protective styles give me knots and tangles too. I left some twists in for 4 days recently and it was so bad I had to get my scissors out. For my hair under manipulation is more of a problem than overmanipulation.

Yes, I've actually considered this. I wish I could do twist-outs but I wear a surgical cap at work and my hair would be a mess at the end of the day.
I haven't hennaed for about a year. I use Qhemet Burdock butter on my hair, and moisturise about twice a week. The twists stay in for 2 wks and I wash with Shea moisture weekly. I always thought leaving my hair alone in twists would help with retention. Now I'm just puzzled. I honestly don't know what else to do.
Thanks for all your responses