I don't like the idea of overpaying my taxes to the IRS by up to ten percent for the year, hence no safe harbor scheme.
I also prefer to have certain financial things on "cruise control" as the years wear on. Hence my decision to do monthly withholding from all retirement income streams, not just RMDs.
Toward the end of each year now, the only thing I do financially is compute and do a Roth conversion to get my AGI up close to, but not over, the next higher IRMAA tier threshold (projected).
Then in February, along with doing my income taxes, I might adjust my withholding by 1% or so on certain income streams.
My goal is to owe the IRS a few hundred $$ in tax each year rather than get a refund, a better situation in the unlikely event that I have an identity theft filing...