Door Jamb to Wall

[Alaskan Son]

I was a framing sub for a number of years before becoming a GC and also a designer. Production houses we usually framed the rough opening exactly 3 inches from the corner, or 4 inches to the actual door as you suggest...

Custom houses and jobs where you have more room to work with, I would recommend 6 inches to RO. At 3 inches there's a chance some wider mouldings won't fit, and even if it does fit or you use standard casing, the painting/staining work at that corner is often hard to do right and ends up a little sloppy.

Just my $.02