Backroll problems

I keep throwing a mexican backroll every time. only about 1 in 8 i seem to roll. here is the deal. a few years back i hurt myself very badly trying a backroll. i come in like i was doing a raley went about 20 feet into the flats, out the front, hyper extending everything from my toes to my head! it hurt bad. back still not right. anyway im trying them again a few years on. i can do the usual stuff like toeside backroll, tantrum ect consistantly but backroll attempts i come in on a progressive edge and everytime i hit the wake i buckle at the waist! ah man it sucks i always throw the handle as my board hits the water(not because im scared) i know never to let go of an invert, im so disgusted as i do not want to throw an ugly MEXICAN of course unless its to blind then its wikid. Most of the time when i dont buckle at the waist i release off the wake AND THE ROPE STARTS GO SLACK??? again i think ah man here we go again ad chuck the handle.

i understand progressive edge and have taught a few people to backroll but i cant see myself. i dont know maybe its just the fear makes me screw up. its a basic trick but scares the hell out of me. tried throwing the board behind, looking up, looking back, there must be one fundamental reason why the line goes slack.

Sounds like your flattening out at the top of the wake and loosing tension in your line. You dont really need a huge cut for a backroll. I usually go 10 or 15 feet outside the wake and make a short and hard cut keeping the handle low at my hips and just concentrate on throwing the board away from the boat, standing tall at the wake, and looking over my front shoulder. Standing tall will help too because it shoots you straight up and right on the other wake for a clean and soft landing. If you wanna bring it further out into the flats then just take a longer cut. Just try not to make a long cut and short one and that might help you.