It would be interesting to conduct underwater surveys around the area of the Grand Banks. That area was a huge island, bigger even than Newfoundland is now, back then, according to the map. It is also much, much closer to Europe via the proposed Spain/France/Sea Ice arc of the Atlantic. The big problem with the Solutrean blade to Clovis point transition is the 7,000-10,000 years that separate them. But suppose the Solutrean Cro-Magnons lived peacefully on the Grand Banks Island UNTIL the rising sea forced them to the North American shore. If the Maritime provinces, New England and New York were too barren due to the recent ice melt, it's only natural that they would move Southeastwards--smack into places like Topper, Cactus Hill, etc. Interestingly enough, these sites have some of the EARLIEST Clovis remains. Not New Mexico or the Southern Plains but the Southeast USA.
The only problem with diving the Grand Banks is the extreme cold and the possible snaggings by fishing boats!
But, wouldn't it have been under ice 10,000 years ago? (The Gulf Stream wasn't flowing back then to keep it warm, right?)
The last big Ice Age 'melt-surge' occurred between 7-8,000 years ago.