"Perhaps the numbers I remember came from Vietnam. Statistics out of Asia are iffy at any time :-)."
You've got that right. Its in the communists' (or however is the ruling group) interests to put out twisted numbers when it comes to tribal people.
"I don't know about the situation in Laos specifically, but a Catholic Hmong here told me that the translation of the Bible put out by Voice of the Martyrs for the Hmong recently wouldn't work for her congregation, because it's a different dialect of Hmong ... presumably the one mainly used by Protestant Hmong."
That doesn't surprise me at all. Most of the dialects are entirely different from each other. The area is very tribal. In Laos alone, before the Pathet Lao takeove,r there were something like 67 separate and distinct tribes and linguistic groups. After the takeover there are about 45...the remaining 22 having "disappeared", with a little help from the Pathet Lao butchers.
Very interesting information, thanks! You've been in Southeast Asia? When?