The part about spotting the oddball only after seeing the normal ones enough times hits home. This is just how learning works anywhere, not just with cameras. A nurse who has taken ten thousand blood pressures instantly knows when something feels off, but a brand new one has no clue what normal even feels like yet. Same with a cook tasting soup, or a mechanic listening to an engine. You build up this mental picture of "fine" and then anything that doesn't match it kinda jumps out at you. That's why the 37th one teaches you more than the first 36, the first 36 were you building the picture. The weird ones are only weird compared to all the boring ones you already know by heart, so basically you have to earn the right to even notice them lol.

Five months seems like a long time to pin down smoke quality, but I am not sure it is as big a deal as you are making it. Plenty of folks run dirty smoke on purpose and still turn out ribs people fight over at the table. The gray bark you are describing might bother you, but most people eating it would not know the difference unless you pointed it out. Waiting 15 minutes for thin blue smoke is fine if you have the time, but some of us have jobs and kids and cannot babysit a chimney starter all afternoon. You found what works for you and that is great, but calling it wasted time feels like a stretch. Half the fun of this hobby is messing up and figuring it out as you go.