In my opinion, your etymology is no less idiosyncratic than Isaac's.
1) Tet is not "probably" a reflex of Taw. Tet is no doubt NOT a reflex of
Taw.
2) The root PTR "to interpret" in Modern Hebrew is from Aramaic. The
equivalent
Hebrew root is P$R, indicating the original NWS root is p-th-r. /th/
(as in English
"thin") developed into Shin in Hebrew and Taw in Aramaic.
3) The root R)Y is a triconsonantal root.
The use in your theory of the term "Afro-asiatic" is inappropriate as
you only take
into consideration Modern Hebrew. Indeed, the moment one includes Aramaic and
Arabic (both in Central Semitic) one sees that there is no "widespread
Afro-asiatic
root PTR" or "widespread Afro-asiatic root R".