Thanks Phil,
The hairs I drop now don't have the 'taper off' in diameter, they're equal in diameter, and sometimes with yellow ball at one end. So the hairs are not getting weaker. Based on your experience, these hairs might not belong to the 'bald' area. So I think they might be the newly planted hairs. I do observed that the HT hairs are getting fewer and fewer, in a slow rate.
When I did HT at Bosley, there're 2 people planting hairs (one on left and one on right). Now the hairs on my left side are dropping, I guess it's because of his poor work?
So I'm wondering if these planted hairs will come back, or they died completely. It's hard to see new ones coming out