> There are two issues involved
> here:
> 1) Lineage
> 2) Doctrinal affiliation
>
> So one can belong to a certain lineage and still hold to different
> doctrinal views.
Precisely -- this has always been the case, but some people don't seem to be
able to get their heads around it. It is noteworthy that Xuanzang even
mentiond Sthavira Mahayana monks, thus indicating their Vinaya lineage and
their doctrinal position.