Connecting to a weight attribute - best practice?

Specifically, I have a multi attribute, indexed by vert #, that I wish to use to drive the per-vertex weights for a blend-shape.

Currently, I’m doing this with a script that simply goes through one-by-one and makes connections from each indexed plug in the first attribute to the the corresponding indexed plug in the second attribute - ie, one connection per vertex.

While this works, it seems weighty and kloodgy… and I’m afraid performance might be an issue with meshes with a high vert count. However, I’m not sure how else to accomplish the task, given that connecting directly from the first non-indexed multi plug to the second doesn’t work.

Is this the way that this task is commonly done? Is there something I’m missing?

Thanks in advance…