You imply Ajahn Brahm perhaps. But who else "were formerly in the Ajahn Chah camp but then moved onto other pastures" ?
It wasn't Ajahn Brahm whom I had in mind but rather those monastics whose withdrawal from the Ajahn Chah scene was their own choice. For example, the American Ajahn Sumano, formerly of Chithurst but now living alone in Chiangmai, the Aussie Bill Platypus, who began at Wat Pa Nanachat but then disrobed and switched to the Dhammayuttika Nikaya, and then all the western breakaway nuns (I don’t remember any of their names) who started out with Ajahn Sumedho.
Any thoughts on why there are so few western disciples setting themselves up as teachers,
I think that in part it’s due to the type of people who get drawn to the forest tradition. The preponderance of them are pretty introverted. But mostly it’s due to the fact that few of these monks regard themselves as qualified to teach. I mean in the forest tradition in general the idea is that teaching is the preserve of spiritual virtuosos —monks with high attainments— and until you become such yourself it’s best to keep your mouth shut and not take on responsibilities that are likely to distract you from this aim.
In the Ajahn Chah tradition it’s different because there the monks don’t really have a choice in the matter, but are pushed more or less willy-nilly into teaching positions.
or why so many have disrobed for that matter?
Doubt, loss of faith in the Dhamma, despair about their capacity for progress, sexual desire, boredom, depression, culture shock, homesickness, ill health, pārājika offences, long-concealed saṅghādisesa offences, aversion to Thai people or food or climate, contempt for their fellow monks, family problems, etc., etc. Besides these there are an extra two reasons that seem to be peculiar to those living in the west. One is an uncomfortable feeling of alienation from the surrounding culture; there are moments when it just seems so absurd to be walking around a modern western city in an ancient Indian ascetic’s garb. The other is that it’s a great deal easier for a monk to get burned out than it is when he’s living in Asia.
I recall reading that in the Thai sangha as a whole, the proportion of the monk population at any given time who will remain in the robes for more than a decade is about 7%, while those who will be monks for life amount to less than 1.5%. So statistically it would appear that disrobing is really just what comes naturally. The oddballs who don't disrobe are the ones whose behaviour needs explaining.
Yes, as far as I know Ajahn Dick Silaratano is the abbot there.
Thanks for the news.