1. Yes it is possible to slow down the process in early stages. 2 In balding there is miniaturisation of hair follicles due to hormones especially in males. The follicles do not die immediately.
3. The recovery of the follicles depends on how far the process has progressed. Its always possible to slow down the process. 4. Hard water affects the hair shaft and not the roots. 5. The hair that you see on surface is a dead keratin structure which can break off if already weak and thin. Keeping the hair clean and at the same time preserving the delicate shafts has to be balanced well. 6. It is beleived that the grafted follicles are resistant to effects of DHT so can function normally. Also balding is a progressive condition so even after transplant maintenance treatments are must.
7. Once the Follicles are dead, they are dead! But there is no way of knowing which ones are dead and which are active.
Next Steps
If you have started to lose hair then starting treatment in early stage itself is advisable and it needs to be continued as long as you desire to have head full of hair.