Loran, like many things related to planting, there is just no concrete answer.

I think the best guide is that you said you had your best stand ever last year with your Curvetines set as they are.  "If it ain't broke don't fix it" comes to mind.

The thing to do again as every year is to check there is little to no lateral play in your tailpieces, or row units for that matter. Parallel link bushings also affect the ability to keep the closing wheels centered on the seed.

We space them out a bit further to be a bit cautious for those folks that are crabbing more for various reason.

Summary: grease your Curvetines, check for side play and you should be good to go.

Jim at Dawn