As well say that Hermetic Magi don't get to say what a form and effect bonus is.... Turning a Sympathetic connection into an Arcane connection seems a perfectly fine extrapolation of Hermetic Magic to me. Again, Ars Magica has "The Limits Of Magic" clearly spelled out, and this doesn't seem to run into any of them.
Ancient Magic, Integration, and Original Research are a big part of Ars Magica Fifth Edition, with many supplements having canon values for the points needed to add such things to your game. Blowing that off as "not canon" seems to deny the biggest change in this edition.
I never said that there aren't suggested breakthroughs in canon, in fact quite the opposite. But i did, and am now, strongly saying that they are suggestions.
IMS: The apprentice's gift would count as an Arcane Connection to their Master for a brief time (similar to a tattoo being a connection to the tattoo artist) after the opening of the arts.
Other than that I don't think you can really get an Arcane Connection out of them