Online defensive driving?

I was looking at this today (I have to do one too)... I figure I'll just use this one its 25 bucks and for another 25 bucks they send off to get your driving record

http://www.texasonlinedriversafetycourse.com/?COUPON=EDTXDCS&crtag=Google

My wife did the blockbuster one. Took about 6 hrs. $10 to rent the video, $30 for online and mailing. I guess it was pretty easy. She did it on a sunday.

http://www.dfwstangs.net/forums/showthread.php?t=398105&highlight=defensive+driving

I took my last 2 defensive driving courses through defensivedriving.com for $25. Don't waste your money having someone else order your driving record. Do it yourself online for $12. Takes less than 5 minutes, is mailed directly to you and you have it usually in less than a week.

https://www.texasonline.state.tx.us/tolapp/txldrcdr/TXDPSLicenseeManager

wouldn't take it any other way than online. Think I took it at defensivedriving.com.

Alright but how does it work, I mean do I take it and then take the certificate when I pay my ticket? Or do I pay the ticket first? Also why do you need a MVR, for proof that it was wipe off your record or something? Thanks