Leafminers burrow between cell walls. This means they are protected from pesticides. You can use a systemic for vegetables from Bayer, Ortho, and other companies. Not necessary unless you want pretty leaves. As said here before, we eat the fruit not the leaves. Aim for pretty fruit. This link gives you detailed info on the leafminer and has a photo of your leaf! Here is a link that might be useful: American Serpentine Leafminer

Not virus. How many leaves are affected? (I don't see many in the overall images.) Most often, it's only the older leaves I'm not familiar with the ferts you use. Why are you using light doses? It's better to follow label directions.

Forgot to mention it, but you can see it in the photos, the veins of the Early Girls especially, but on all the tomatoes in general, are purpleish. The leaves aren't turning colors, but they're kind of tough and leathery. I'm starting to feel like a garden hypochondriac. Every time I look up a new tomato disease or pest, I'm convinced that's what I have, so I'm hoping you all can help me narrow it down. After looking at pictures, I'm thinking maybe the bugs are thrips, and maybe they've spread TSWV to the plants, but some of the physical symptoms of TSWV don't sound exactly right on the money. I'm so confused. I always thought gardening was so simple - throw plants in the ground, water, voila! Not so, I'm afraid. Soooo not so.

i doubt it ... more like individual cells burst.. which sometimes happens with excess rain ... i am pretty sure there is a tomato forum .. where the real T kooks hang out.. lol .. just keep in mind.. about 99% of that leaf is still functioning ... so at this point its only cosmetic damage ... and i am thinking.. those are the lowest.. oldest leaves ... what do the newest growth point look like ... that is where i look to see the vigor of the plant .. or the newest of the bug .. if any ... ken