It's not as obvious as you'd think to just withdraw from your taxable until the calendar year you're 59.5, and then start withdrawing from your retirement accounts. The reason is Required Mininum Distributions (RMDs). When you hit 70.5, you're going to be forced to withdraw increasing percentages of your money in tIRAs every year. The RMDs that come from your traditional accounts will be taxed. Now remember, if you avoid withdrawals from your tIRAs until 59.5, that's 11.5 years of unhindered growth your tIRAs will experience. It is possible that you may end up with a large enough balance in your tIRAs that it will force you to withdraw more money than you wish to spend in a year, resulting in higher taxes paid than you'd have otherwise paid.
Hence, it can make sense to execute the
Roth conversion pipeline, while skipping step 5. But you should only convert a small amount each year.
I don't know which state you live in. If you live in a state without income tax, then the amount you should convert each year is the total of standard (or itemize, if you itemized) deduction + exemption. Then withdraw only shares from your taxable account that only have long term capital gains. This way you can pay nothing in taxes, while still selling shares in your taxable account to live off of and converting money from your tIRAs to Roth IRAs to avoid future RMDs.
Go Curry Cracker has a
more in depth explanation of what I'm talking about.
Furthermore, if you do live in a income tax free state, you should also do
capital gain harvesting, which Go Curry Cracker mentions as well in that post.
If you do not live in an income tax free state, then whether you should do these tIRA to Roth IRA conversions is less clear. You'd have to do the math on the state taxes you'd pay for the conversions and compare that to your projected RMDs when you hit 70.5. The equations shouldn't be complicated, but the issue is you have to put in a guess of investment returns in your tIRA, since the taxes paid because of RMDs is going to depend on your future tIRA balance.