I think he/she wants to get rid of the pop all together. With your method you will still get the text popup. The only difference is that you won't see any of the message contents in the message, It will just show the sender's name, with the words "Text Message" underneath, hence, the "Show SMS Preview" setting that was turned off.
THe iPhone is not Player proof like the 8800 series blackberrys. iPhone are not made for hiding Apps, IM's, and SMS yet! Well, I hope it is a yet! lol. THe old software did allow you to adjust so you can see "Text Message" vs now "Text Message, meet me at your house babe for a happy ending" lol Playa Proof the iPhone please!
"player this", "player that". What's so cool about cheating on your bf/gf? I don't get it. Mess around all you want, but at least be honest about it. Real players don't cheat, anyway - they don't have to, because they can be straight up about who they are and what they want, and still GET what they want. Only losers have to lie and hide and cheat to get what they want.