This simple device is the most usefull thing I have found for training yourself to shoot properly. I took lessons from Rick Welch a few years ago, and my shooting improved greatly. However..as of recent I have been falling into bad habits, and my shooting has suffered. You wanna fix bad habits? Try one of the formasters out. I made my own. Pretty simple. I thought I was having problems with back tension...since my shooting has suffered. When trying the formaster, I found that this was not the case. My back tension has not been the issue...but rather my release hand, and my bow arm. I have been able to maintain back tension, as showed to me by the formaster, but my release hand had a bit too much tension. Also, I found that my bow arm was moving alot due to peeking. The formaster...or a similar homemade device will show you this and correct it in short order. I used the formaster for over a week without shooting an arrow at a target. The painfull consequences of not shooting properly quickly whipped me back into shape while using it. I finally shot at a target tonight...and achieved the accuracy that I once had. However...I'm not done with the formaster. I'm going to keep using it daily from now till season to attempt to ingrain the good shooting habits that I once had, but lost. For the money of either buying or building one...you gotta try it!