Thanks for your comments. I hope this comes off as helpful rather than pretentious, tho I always fail at this sort of thing.
I am fortunate that I work for myself, therefore I can throw time at the problem. I work from 5AM to 10AM, and get out in the day on the days I can. No magic, really, just luck. If one wants to measure these sorts of things, it would be silver per hour per historical population density. We're lucky to have historical population density around here, otherwise I have no desire to measure these things. Its not a competition. For me, it is the beauty and purity of the game, sort out historical outdoor puzzles (I have a background in writing outdoor puzzles, and am in the process of writing an "armchair treasure" hunt); the silver is just proof you have solved another puzzle. More important to me is the number of _sites_ I have found silver coins at (167, or an average of about 9 per site)
My best site is a regional football field that dates back quite a long time, but was off-limits until they decided to re-sod it. I found 142 silvers there when the project started. I was there 10 hours a day, literally as the bulldozers were bulldozing. On big sites I just throw that sort of time at it if I can. I think we all do that, some are lucky enough to find the big sites.
I'll do any site, even if I think it has one silver. I had a site, a 1950s house, that was taken by imminent domain to build a freeway exit. I found one silver there, but while there, saw another site, and said, well, that looks promising, and found 125 silvers at the next site. Its all luck. I still do 1950s houses that may have one silver. Its all in the joy of the hunt.
My sites vary, but I will not do anything illegal or without permission (e.g. Fairmount Park). My life motto, more than my MD motto, is "have no boundaries, but fiercely respect others' boundaries". I think that can apply to metal detecting once in a while.
Specific things that work for me --
1) use an E-Trac for silver coins. Its the machine, not the man.
2) to paraphrase Indiana Jones -- "most silvers are found in the library". I spend more time on research than in the field. Research can be boring, but I personally enjoy doing it (back to the "puzzle" point). I learn cool stuff that interests me that does not apply to metal detecting.
3) keep good records. You'd be surprised at the insight that comes out of good records
4) efficiency, efficiency, efficiency. Everything you do in every aspect of the hobby must be as efficient as possible. While my big problem is with pinpointing, and how inefficient it is, the biggest problem for alot of people is how they attack a site. Wandering a site for a couple of hours is almost always the most inefficient approach. Attack it from the edges or were research says the goodies are. Tight grids rather than random wandering. Look for tells, such as deep 70s clad and deep bottlecaps. Learn the sound of a site. No deep clad or bottlecaps, consider the fact that the evil Fill and Grade twins have been there. Such sites sound different and have different tells. Know when to bail on such a site and go elsewhere. OTOH, once a site gives it up, throw all you have at it. Learn to read the grass and trees, and other tells. This just takes practice and luck.
HTH. I obviously can't give up my sites, but I can give up a redacted distribution of them. This is easy in Excel. I don't track silvers by type of site. I doubt this distribution will be useful, but it may be. WDIK.
HH