Within the SOP solver is a VOP node getting the the point position of the geometry and subtracting is from the viscosity attribute then re-binding to the viscosity attribute. Never thought of the reason for that VOP network, rather I wasn't aware you could use SOP within DOPS.

You can look at the scene to get more info, I'd really like to know how I can do this without using a wrangler as well. I understand attribute create / promote may be part of the plan but I'm not sure ?

Sepu - You say there are other ways to do this, what are those other ways ?

Well what you did in the Sop solver didn't make sense to me at least. You can do similar stuff change values and bring data from Sops to Dops as well.

You can do all that I did in the wrangle with an Attribute create and a color node, to me is just easier with the wrangler.

You can also do by grouping objects and make a group for ex: like “viscos” and “noViscos” you can try with a bound, expression, etc. There is many ways to drive attributes in Houdini.

Just try different things and have fun.

Bound node for isolating group points as to not be effected by a DOP ?

Yes for example that is one of many options.

I should have asked, how exactly does this work ?

is pretty much the same deal, just in the wrangle you will add the group name that you want affect. There is a lot of ways of interacting with attributes. You need to play, trial an error.