YouCanDoIt

The comment regarding immunization risk is correct. By cash flow matching, you effectively use zero coupon bonds to match the cash flow liabilities, and therefore removing all the reinvestment risk.
The comment about less capital to fund the cash flow matching is not correct. This is because you will have to purchase a zero coupon bond for exactly the amount and date of the cash flow liability, this can be expensive because you have to buy from a limited pool of bonds regardless of liquidity..