Tony, thanks for chiming in. And no need to explain the drinks. Any excuse will do for me when I want to have a few cold ones.
I can't use the "it's hot" thing though as it's bitter cold here right now.
I will now be trying to balance in the tracking all metal mode before flipping to PP, to contrast them and see if the depth gets even better than it's already outstanding job it's done at some of my real bad soil/sand sites. Can't imagine it getting even deeper than it already does with volume/sensitivity at full, but man if it does...
I prefer the pump method in a clean spot to set the balance in tracking before flipping to the fixed all metal mode when I've used it. On prior machines with tracking I always found it threw off the ground balance a good bit when I was sweeping around over iron and such, which I never used tracking much anyway as I prefered setting a fixed balance to not risk tracking out deep targets.
On the WOT/SEF thing not being able to run at full sensitivity with PP...Haven't had issues with full sensitivity in PP with the 12x10, and often in disc I can even run full blast manual sensitivity with it too. Very stable coil. Was able to run the 13" Ultimate loaner I had at full blast manual at EMI-low sites, but it was a tad bit unstable where as the 12x10 was rock solid when I switched coils to compare. Are you talking of the 15x12? Had one. Deeper than the stock 10" Tornado in my mineralized sands, but not as deep as stock in my mineralized soils. Couldn't figure that out. The 12x10 is deeper than both in both sand/soil sites for me.
As a side note, this quote from Minelab might have answered a question I have had..."
So if you are searching in Discriminate, and flicking over to All-Metal/Pin-point, it may or may not be noisy depending on ground conditions, and the last Ground Balance setting in Track."
By the sound of it, that seems to imply that all metal fixed mode does indeed hold the last ground balance it was set at, even after flipping over to disc and then back to fixed all metal mode or PP. I had wondered about that, since I wired a remote PP switch trigger on my grip...If I needed to re-balance in all metal tracking mode again before flipping over to fixed. I can set the stock switches to what modes I want to flip between and then use the remote PP to keep flipping back and forth to those two modes. A real time saver for reverse discrimination hunting on the beach when I'm in the mood to do that, mostly switching between PP and disc. Still not sure that's what they are implying above, but I plan to test that out in some really bad ground and see if when I flip back to Fixed or PP if the machine seems to have got noisy, having lost it's balance. Your opinion on that?
PS- Even when not running full blast sensitivity in PP, but rather what was stable for disc, and even with the volume all the way down as I prefer with my headphones in disc, PP was still punching much deeper than disc at one badly mineralized beach. And I mean not just as deep as the 5 or 6" disc was choking on due to the ultra bad mineralization, but rather much deeper. But yea, full sens/volume does show me more depth in PP, while lowest volume for me doesn't seem to cause disc to loose depth.
When I was testing out the loaner 13" Ultimate coil at a land site, I laid it down while the machine was still in PP mode, and was shocked to find out by accident as I grabbed my digger that PP/Ultimate was sounding off to my digger all the way behind the arm cup. I don't often use PP to pin point a target, as I can do it just as well in disc most of the time and prefer disc for that so PP doesn't drag me off a coin into some nearby iron or something. I had even pointed the digger at the coil so it presented a bit less of a image to it and it was still easy to hear it well behind the back of the arm cup. I'm a tall guy so my custom shaft is rather long. I bet the 12x10 would do equal depths in this "test" with the digger at full volume/sensitivity.
But anyway, man...can you imagine the implications for using PP and a larger coil like the 12x10 or Ultimate for cache hunting or large relics like canon balls? Not saying it'll get that kind of depth in the ground but just the same it might do some serious damage as a kind of cache/larger relic hunting beast. PP has shades of perhaps living up to the stellar depth claims of certain "ultra deep" speciality detectors used for coins and such, and with many of the same abilities (being able to tell iron from non-ferrous stuff), along with modulated audio that some of those machines don't even have. I think the thought of that possibility is pretty cool. A third machine lurking under the GT control box, and very similar in certain traits and abilities hinted to about those types of machines.
About your remarks of seeing what works in your own soil or sands- Yes, vital that various opinions or advice be proven or disproven for one's self in their own soil and specific mineralization. I have found, for instance, that the old rule of thumb that a super slow crawl with the Sovereign gives best depth just isn't the case at most of my soil/sand sites. I've tested this extensively on undug targets at fringe depth before recovering them, and found if I crawled at the turtle slow pace (say 4 seconds per sweep) often said to give best depth with a Minelab, that it simply won't even see the target at fringe depth. I have to increase my sweep speed (and this is in disc mind you) to about what I would call a medium speed for my Whites.
Now, is that my minerals, the 12x10 coil I'm using, or some other factor involved such as my sensitivity level I'm using on that day? Can't say for sure, but I've seen this happen on both sand and soil at I'd say 90% of my sites, in both good ground and bad. And I'm not talking about the fast wiggle or constast/fast short sweep many of us use to derive the hardest hit on a deep target to pull the best tone/ID out of it, but rather just a long general "looking for my next target" swing.
That's how I test it to figure out what speed the site wants for best depth/hardest hit on fringe depth stuff when I come across one. Often it's a pretty fast sweep (for a Minelab), and even at that faster pace I can unmask stuff right up against trash or iron. Only thing I can figure is maybe it's the 12x10 coil that makes the need for a faster sweep, if not my soil. The DD line on the 12x10 is so laser sharp that the increased speed doesn't have any issues with left/right unmasking separation, but of course proper investigation still requires I stop and wiggle at two "as one" targets to be sure about what I'm seeing.
I been using my GT only 4 years and i do not consider my self a expert by any means i just do what has worked best for me . Jim 
