I can do like 5 different inverts (not tooting my horn I hope) and the backroll, which is supposed to be the easiest, is still the most inconsitent for me. I used to think I needed to really throw the rotation really hard because I was so freaking afraid of landing nose first. I have since learned that it is, and should be, a very smooth and relaxed flip. Try to concentrate on getting really good pop off of the wake. This will allow you to float your rotation a little more and, as a result, you should have more control, both in the air and on the landing. This has helped me alot but it is still a 1 in 3 type trick for me. Keep trying and try not to get too frustrated this sport was designed for fun, or was it pain?! Oh well good luck and let us know when you stick it!