Steg Belsky scripsit:

> And the
> /m/-/s/ juncture seems to attract an intermediary [p], [tSampski].

This is typical of English, as shown by the common surname "Thompson",
which is "Tom's son" with an intrusive "p".  (Hi, Carlos!).
Ditto "Sampson" < "Sam's son".

Then there's Nim Chimpsky (not Chimsky), one of the first sign-language-using

Her he asked if O'Hare Doctor tidings sent from far     John Cowan
coast and she with grameful sigh him answered that
O'Hare Doctor in heaven was. Sad was the man that word
to hear that him so heavied in bowels ruthful. All      [log in to unmask]
she there told him, ruing death for friend so young,
algate sore unwilling God's rightwiseness to withsay.   _Ulysses_, "Oxen"