I get your thoughts. Due to shoulder issues I played offhand for a few months.
I wanted to simplify movement as much as practical, particularly ant fine control. Focus on the major elements. Definitely limited the effort to standstill.
I felt I could develop a decent drive and mid game at about 80% of my dominant arm capability. Probably close the gap over extended time.
Fine motor control such as putting seemed like it would take a lot more time to even get okay at relative to my dominant arm.
BUT, everyone is different in this. Some people have almost no ability to train their non-dominant arm and some are ambidextrous, but even that can be limited.
There's a Euro DG player that throws RHBH and LHFH (I think—it may be opposite that ). Regardless, it seems really odd.
Bottom line is only you can resolve the amount of effort required to develop your offhand.