To bedifferent:
What I mean is that don't you think it is foolish to defend something while you know almost nothing about it? I don't think the question that who is the first people to climb Mount Everest is comparable basic geographic knowledge about a place you defend. You are either quibbling or logically confused in my opinion.
Your concern of "they are afraid in 200 years to be 5% of the populartion of Tibet" doesn't stand at all. Due to the unique geographic feature Tibet holds, other ethinc group is unable to root there. Yes, there are many Han and Muslims people there, but most of them are just making money there and not plan to live there forever.They are not used to live in a place of such high altitude.Yes, Han people did settle in many other places around the world, but Tibet is a unique place. If you don't believe my words, you can try to live there for some time. Further, most of the "immigrants" live in big cities, for the countryside, it's still tibetan's world.
I can see that you pay sympathy for tibetan people because they are kind "pure". However, I wonder whether you will be kind of disappointment after you getting to know more about them? They did change a lot, at least those in town. But they are not changed by others (you are right in this point) but themselves!
This March, BBC has promoted a 5-Episode documentary: A year in Tibet. There is no Chinese official accompany during the shooting so it is quite "free", and instead of being political, that documentary just focus on daily life of average (or below average) tibetans, I think people can learn a lot through it. They are just human beings like us. I do think the government has made some mistakes especially during the Culture Revolution, but it is now trying to make compensation. However, the west focus on the past and be blind to all efforts made by the government and common Chinese people, this is what make Chinese angry.
Anyway, thank you for the reply, actually, forum is a place to exchange ideas, we are not forcing others to accept our ideas, but just giving out our voices.