I was just thinking that there wouldn't be enough support, but since I have never tried the bucket I just run every thing through my thoughts. Still looking at this because it's a great idea.
The journal ISK linked you up is one of the finest examples of growing Hempy bucket using Lucas formula I have ever come across. I highly recommend it. I do things slightly different than him, like no soul caps for instance, and always get good results. It almost takes effort to do get it wrong.
I've been doing hempy for several years now. I use the same Perlite mix, I believe I may have added a little vermiculite to it, over and over for I can't remember how many grows. Before Hempy i grew soil a couple of times and bought a nice water farm hydro setup that I also used a couple of times. Hempy is by far easier faster and cheaper taking far less of your time and effort than either. Seriously, unless u just want to hassle with your grow all the time(hydro) give it a shot. Really, there is absolutely no reason to be intimidated by this method like it's complicated or some type of rocket science. Easier than paint by the numbers if you have the right model to go by. Best of luck bro.