I didn't get to attend Kevin Hogland's seminar, but have seen the video or post he put on Minelab's site regarding VA soils and timings. After seeing that, the last time I was in VA hunting I tried a bunch of different timings (mostly focusing on sharp, normal, fine gold). To my surprise I really did not notice much change in depth in any of the timings. I switched between sharp, normal, and fine gold and when a target was found would try the other two. For the most part, depth did not seem to increase. What was interesting was this.... in one timing (say, sharp for example) a moderately strong target could be heard that which not be heard using another timing. But this did not seem to be specific to any one timing - each timing would ignore some targets. I found more in fine gold, but I think that was only because I was more used to how it responded to targets than in the other timings.
Since that time I picked up Jonathan Porter's 5000 video. In it at one point he demonstrates something similar in the gold field with hot rocks. I'm thinking to get everything a person probably has to go over each site in several different timings to "get everything". If I only had to pick two, I'd probably use sharp and fine gold at this point.
But next time I expect to get more depth with the newly purchased 15x12 DD.
On the PA site mentioned above, I tried all of the timings and none of them would settle down completely. Only in Sensitive Smooth would it settle down to the point where I could for the most part hunt with it, but it was still noisy. Another thing gleaned from Jonathan Porter's video was his simple explaination of how to tell the difference between EMI interference and ground noise. I felt real dumb after hearing the simple explaination, but that info will help determine the issue at the local site... I need to go back and try one more time, if nothing else for the learning experience.
Thanks!