I am in a strange situation where I did not know about the pro-rata rule. I never made over the roth income limit until a couple of years ago, so it was never previously on my radar. I suspect that this type of mistake is common and I assume is part of IRS's design :P. The answer may be that it is not worth doing anything, but I thought some extra sets of eyes could help.
Situation:
Me: Rolled over a ~ 310k (current value) 401k to a traditional IRA earlier this year. There was nothing wrong with where it was, I just thought rolling it over was what you do as that is what I had always heard, and I had left the company a few years prior. My new employer 401k had higher fees, so I thought a rollover tIRA made sense. This rollover was pretty much an immediate in kind transaction since the 401k was with vanguard. I am not sure what my options are here. I could probably roll the rollover IRA into my new 401k, which has a little bit higher fees, but the bigger risk I see is that I would probably have to take the money out of the market for a period of time. Since it is a decent sized account, it may not be worth the risk, especially since the new account has higher fees (0.4% ish for sp500).
Partner: Will probably go over roth limit next year per IRS. Partner rolled over 50k years ago from a prior 401k, but then rather than keeping the rollover account separate, partner added some additional tIRA contributions to the same account as the rollover. The account is about 100k total. Partner has a great 401k. Would a rollover be possible when the rollover portion and personal contribution portion is intermingled in the same account?
Note, I see the backdoor roth as a nice perk, but since the max contributions in an ira are quite low, taking on a lot of risk with moving accounts may simply not be worth it.