The biggest problem is the basic premise that a successful Vinland won't affect Europe. Here is the problem as I see it.
There was at least sporadic contact between Europe and Greenland until the early 1400s. If Vinland was a functioning growing colony during this time, the merchants coming to Greenland would know about it, both from the Greenlanders and from the Vinlanders, who no doubt would travel north to Greenland to trade. Once the merchants knew of Vinland, they would travel there also, because no merchant will give up the chance to make a buck.
The merchants would come, because Vinland could and would supply them with many new world products, mainly walrus ivory, furs, and gyrfalcons for the nobles. They could trade iron tools and weapons, wine, and probably knowledge. In addition, if Vinland was welcoming immigrants, or even if they weren't, the merchants could take settlers from Europe, either openly to a Vinlander port, or covertly to a portion of uninhabited coastline.
If Europe knows about Vinland, the entire exploration of the New World would be very different, especially if Vinlander explorers shared their exploration knowledge with the merchants. You could see European merchants contacting the advanced cultures of Mexico much earlier that Cortez, maybe as early as the mid-1300s.
I know you wanted butterfly nets, but I think these nets would fail, in keeping the knowledge of the Vinlanders away from Europe. As it is, I am relatively sure that Columbus had at least an idea of Vinland when he left Spain in 1492 since he was in Iceland in the late 1470s.
There was at least sporadic contact between Europe and Greenland until the early 1400s. If Vinland was a functioning growing colony during this time, the merchants coming to Greenland would know about it, both from the Greenlanders and from the Vinlanders, who no doubt would travel north to Greenland to trade. Once the merchants knew of Vinland, they would travel there also, because no merchant will give up the chance to make a buck.
The merchants would come, because Vinland could and would supply them with many new world products, mainly walrus ivory, furs, and gyrfalcons for the nobles. They could trade iron tools and weapons, wine, and probably knowledge. In addition, if Vinland was welcoming immigrants, or even if they weren't, the merchants could take settlers from Europe, either openly to a Vinlander port, or covertly to a portion of uninhabited coastline.
If Europe knows about Vinland, the entire exploration of the New World would be very different, especially if Vinlander explorers shared their exploration knowledge with the merchants. You could see European merchants contacting the advanced cultures of Mexico much earlier that Cortez, maybe as early as the mid-1300s.
I know you wanted butterfly nets, but I think these nets would fail, in keeping the knowledge of the Vinlanders away from Europe. As it is, I am relatively sure that Columbus had at least an idea of Vinland when he left Spain in 1492 since he was in Iceland in the late 1470s.