Refute the math if you will. You wish to shoot the messenger instead, be my guest.
Oh, and who did your 23% math?
As for the 23% number, this is confirmed by multiple respected economists with independent studies. From the same paper I linked to you:
For example, Dale Jorgenson (Harvard) has found that the FairTax plan is revenue neutral at 22.9 percent. Jim Poterba (MIT) has found that the FairTax plan is revenue neutral at 23.1 percent. Laurence Kotlikoff (Boston University) found that the revenue neutral tax rate was 24 percent. Researchers at Stanford, the Heritage Foundation, Fiscal Associates and the Cato Institute have reached similar conclusions (22.3 percent to 24 percent).
Meanwhile, you've got one Brookings Institution writer who makes wildly inaccurate (and self-contradictory) claims.