Transferring Attributes from low res to hires mesh, how?

[Spaz8]

So I use "attribute transfer" a lot. But I guess I must mostly go from highres to lowres, or have been blissfully unaware of the shortcoming of going the other way. I am trying to optimize a process by doing calculations on a much lowres mesh, where density is only where it needs to be, and sparse elsewhere. I then want to transfer that calculated data result back and fully populated the pts on the original dense mesh. The issue I am seeing is I am getting basically Leopard/polka dots print in the sparse areas. I assumed that there would be some sort of floodfill or interpolation in the spares areas where there are not as many samples. I think if I am using a large transfer distance/kernel/blend width it messes up the detailed sections. At the moment it feels like I have to try doing transfer in to parts using two groups.. one to the the sparse with settings and on transfer into the dense with its down settings. User error?

Edited October 19, 2020 by Spaz8
typo