Re: Samarkand and Bukhara
Not true. :) seyeds inter marraiges are frowned upon even now, but was a massive taboo back then. if you knew a tad bit about seyed migration history, you would know that seyeds migrated in huge masses for two reasons, 1) due to persecution of thier beliefs of shiaism, 2) to spread the gene of seyeds as far as possible.
For this reasons seyeds settled in deserted areas, and their populations grew from there to this day. If you ask any elder generation seyed they will not only know the history of where seyeds settled throughout, they will also know or have the whole shajarah with them. You can corroborate any shajarah and a fake can easily be detected.
Faking is a not taken lightly in shiaism (considering the zakaat/khums ruling regarding seyeds) or amongst the seyeds themselves. Mosts Seyeds value their shajarah as much as they do thier integrity, so please do not tar all seyeds with the same brush and that too based on such flawed assumptions, because a majority if not all, have pretty strong basis to back themselves up. It was their forsight in living amongst people like yourself, that made them establish the groundwork for a fake proof system knowing well that centuries down the line, their generations will continue to face insecure people who question thier integrity and seydness despite not knowing the first thing about them.