A compelling feature of a 401(k) type retirement plan has always been the opportunity to contribute money from your current income on a pre-tax basis today - let it work for you over the years - and then pay taxes on the accumulated balance as you withdraw it in future. That’s a real attraction to many company owners and their workers. But what if you flipped this - and contributed money to your retirement savings account with post-tax dollars that you invested over time- and then had the oppor...