The Missing Pinfeather?

I have an ongoing fascination with swan-symbolism in Tolkien, and I have been trying to trace the idea from the Teleri with their swan-ships down to the Swan Knights of Dol Amroth.

But I may have just found the missing piece of the puzzle. It just so happens that Tuor, when he found the armaments left behind for him by Ulmo at Vinyamar, was stymied because the shield was unusually long, and tapered to a point, and bore on it a white swan feather on a blue field.

Later, Tuor took this shield with him to Gondolin, where he joined the House of the Wing, one of Gondolin's twelve noble houses.

That shield, seen here, is obviously a knight's shield, rather than the round sort, and the blue & white coloring of Dol Amroth is seen here for the first time. Could the knights of Dol Amroth trace their symbol back not to the Teleri (as I always presumed) but to Tuor and Gondolin's House of the Wing?

Some references, before I go buy the Book of Lost Tales and read the text for myself. (The version in the Silmarillion does not have many of these details.)

Tuor
House of the Wing