I been thinking about this too. I think from what I have been researching, it sounds like most miners are getting about 90% tt return over the long term and their hit rate is about 30%. Not sure if there are any uber miners who are able to get above the 90% tt return and the 30% hit rate.
90% is terrifying, usually this number is used very liberally by people who have no idea what it means, but they like alot to see themselves quoted or something.
Depending on size of amps and finder used, your average cost in terms of MU paid will vary between some 2% to 7%.
Average MU found actually, in the real game these days trends around 3% (presuming a regular carpet bomb of a certain area, without who knows what knowledge about timing, which will inevitably be niche and irrelevant statistically).
So if you put these numbers together, it means that everyone and their mother would run a constant TOTAL deficit of about 12%. At a turnover of let's say 5k a day which is easy-peasy-lemon-squeezy to generate, it would mean 600 peds, for a monthly bingo of 1800§ lost
monthly. Real americano rupia. For every average miner (these are average numbers, nothing to do with "uber"). This wouldn't be sustainable and nobody would mine.
Lower 90%, but still trending to 95% over ALOT of time one will experiment with indoor mining, but that nowadays is almost nonexistant compared to what it was 10 years ago. Other MUs, other system, other turnovers.
Hitrate on the other hand is something directly related to the tt output and is built-in, it has nothing to do with "knowledge". You can react to it, if is low (22 to 26), average (27 to 32) or excellent (32 to a very rare 40). It's the main screw MA are using to determine variance/volatility, because it has a buttload of importance how often an output of 0,5 will appear at an input of 3 (e.g. "tiny" witth 2 nrfs at single drops unamped ores). But you can't change it, it is what it is in a given time, given area for a given avatar.
To reach 95% you don't need supersecret stuff, you need a simple thing: volume and basic reason., like don't overlap yourself too much too fast.
MU on the other hand, yes, that is knowledge and also very important, experience. It's incredibly easy to get stuck with, say, 1k typo or 1k megan only to discover in horror that the bloody thing just doesn't sell, only as a quick example.
So to somehow put context to your thoughts, a bankroll of 3-4k, basic distance of 110 between drops (supereasy to do with lbml), a decent number of drops per area (this is another thing which you will tweak alot with experience), a decent number of drops per day (2-400 unamped, 200 low amped, stay away from amps higher than L3 until you know what you do), a basic super available finder like f212, efs, f105 etc ofc only maxed, log your finds carefully as in tt input vs tt output and a few relevant % stuff, a decent rate of activity in terms of days played, and you are almost guaranteed to hit around 95% tt return at a total turnover of 30 to 50k to give it enough time to average all trends. Wether you will profit or not this is an entirely different issue, but first you must iron your mechanics so to say, subtleties are an ulterior matter. Don't craft too early, don't set foot in lootable pvp, don't set foot in taxed areas, and even if you'll sink 1-200$ monthly for a few months, you will see trends settling down and you will start to figure things on your own. But actual first hand experience in a relevant volume is a must, there is no other way.
And a very personal advice, even if is out of scope of the thread: try to let as much place for hard measurable stats and less to fantasies.