What you are telling people in this post is irresponsible and bad advice. You are correct that term is a lot cheaper than whole life, but you are leaving out the problems with term insurance that whole life policy can fix at any age. Did you know only 2% of term policies are ever paid a death benefit on? You can buy a 20 year term at age 30 but what happens when you turn 51? Buy more term at your current health at 51? What if you get cancer or other health problems that cause you to become uninsurable? Would you rather pay $100 a month for a $100,000 permanent policy and earn cash value, or would you rather pay $40 a month for 20 years on the same policy and then have to buy a new term policy at age 51 that will be $200-$300 a month and even then if you don’t die during that term then what do you have when your 80? Nothing, because no one is going to sale you life insurance at age 80. I don’t think buying term at a young age is a bad idea, but the longer you wait to transfer some of that to permanent insurance you are digging yourself and your family a deeper hole when you live past that term policy and have nothing to leave them with.
Any reputable source will report mutual fund and stock returns as “annualized” figures, which takes the sequence of returns into account. Another term for this is “geometric average”, which again accounts for the order in which returns are received. So while there are some financial “experts” out there touting average returns (cough, Dave Ramsey), for the most part what you’re talking about here is not a factor.