The money you take from your retirment accounts
(Not Roth IRA) will be counted as income. Income covers investment income and earned income.
Bayfamily is just give a thought. He is trying to say that there is no need to go through retirement accounts since the tax system is so complicated. You don't have to take his numbers..., just his thought, then look at your own situation, see whether it's a good idea for you.
Remember, the personal finance has to be be "personal". there is no one method for everybody.