Thank you for your detailed reply!! It is really helpful.
The Roth 401k to Roth IRA conversion you described is especially interesting.
Can you point me to some reference that states the fact that when the rollover is completed the in-plan Roth conversion would still be treated as "conversions" in Roth IRA?
I looked up the "Retirement Plans FAQs on Designated Roth Accounts" on the IRS website, and it doesn't seem to mention this special situation.
