I've been hunting since the early 90's and have owned or used most of the machines out there...Some I've owned include QII, QXT Pro, 6000 pro xl, Garrett Treasure Ace (one of my first machines), Bounty Hunter (80's model, my first), Tesoro Bandido II Umax, around 3 Explorers, Tesoro Tiger Shark, and so on. I've also used or went head to head with the DFX, Fisher CZ6a, XLT, Etrac, GTI series, Excalibur (got my first bust dime-1835 land hunting with one!), and a few others. I just don't assume that what's widely known and taken for granted is a given. I prefer to question assumptions and prove them to be right or wrong for myself before relying on them as fact. Investigating to me is half the fun, and not just in this hobby.
Another thing to remember is that, as I've said many times before, I am not arguing that you shouldn't dig everything in many situations. Places like the beach, low trash sites, and so on are areas where I live by this rule. However, I have many sites I hunt where it would take years or a lifetime to dig every signal, and I simply do not have that kind of time. If I know for a fact that I'm not ever going to be able to dig every trash signal out of an area it makes no sense to me to begin to do that. Lacking that effort, I'm now forced to decide what method of hunting it is going to increase my odds of good-to-bad targets and make even the effort worth trying. Besides stretegicly picking one small section of that area and digging everything out of it (such as a wade pool area), I'm forced to use something to even the odds more in other areas.
I've atleast proven to myself that there is indeed the potential to avoid most of the tabs and still have the potential to find a large percentage of the rings. That's the whole point of why I did the research. Bottom line for me. Unless somebody can show me some proper research done on rings that proves otherwise I'm going to rely on what I found by my own investigation. I've searched the net over the years and the only project that even remotely held some merit was the Fisher test, and even with that I have serious doubts lacking proper information on the testing criteria.
I look at it this way...When playing cards would I bet all out on each and every hand despite what the odds show? Of course not. To win more often I need to develop certain percentages of probable success, increasing the odds in my favor as much as possible. That's the whole concept when selective digging is the only realistic option.