Yes, agree on the index fund para. He certainly could have gotten more then 4% if he went that way.
CPF cannot be used as a retirement fund. The way that it is set up now, it should be used for daily operating account and a separate investment vehicle used for retirement. Every financial advisor in the world, except for the retards in singapore, will tell you that you should never dip into your retirement fund every month for your monthly expenses like mortgage and housing payments. These must be paid via after tax dollars. How can u retire when you keep depleting you CPF every month? CPF withdrawal is roughly 50% of deposits on an annual basis. What kind of shit savings plan is that when u keep withdrawing half of what you put in every year? Coupled with the low return on CPF, its better to use the CPF to pay the monthly mortgage and deplete it that way. And use any other money for a different investment vehicle.
As for paying off the primary residence, dumb move. why pay down a 2.5% debt. Its like saying you are able to get only 2.5% on your money.