Ideological distortions of MSS

[Dmitri]

I am pondering the following question:

Was the text of Pata~njali's Yoga Suutra altered in a deliberate fashion
to accomodate ideological, religious, sholastic, etc. agendas of
the past 1500 years?

The question, I'd like to ask indologists on this listserv is:
Is there a known sanskrit MSS of which two versions exists, those
two versions are different, and the difference might be attributed
to a deliberate editing of the earlier version to bind the meaning of
a passage towards a religious, ideological or scholastic dogma?

In particular, I am interested if the coming of Islam to India
resulted of any re-writing of sacred texts.

Thanks in advance,
                    Dmitri.