I wrote a piece entitled China tests Nepal's loyalty over Tibet for Asia Times. The article’s hook is that hundreds of Tibetans make the dangerous, arduous, and expensive trek from the TAR through Nepal to Dharamsala every year...and over half of them go right back to the PRC after a short visit.
"Returning to oppression" doesn't quite fit the refugee profile of "fleeing oppression".
You’re curious, I’m curious, the Chinese are more than curious as to the motivations and, more importantly, the identities, of these ostensible religious tourists.
It’s an interesting article about an interesting subject: the “gentleman’s agreement”, enabled by US government financial and diplomatic support, which allows the UN High Commissioner for Human Rights to shelter Tibetan "transit" refugees in Nepal and facilitate their circular trek to and from India and back to the PRC.
The unspoken quid pro quo appears to be that, in return for Nepal's acquiescence to the "gentleman's agreement", the West turns a blind eye toward the Nepalese government's efforts to please Beijing by vigorously thumping the "resident" refugee Tibetans who live in Nepal and demonstrate against China.
How long the gentleman's agreement will continue as emigre Tibetans become more militant and China becomes more entrenched in Nepal's politics is...an interesting question.