You're absolutely right, the torquers were used at LEO. I vaguely recall that the GEO birds used hydrazine thrusters for station-keeping. The GEO gear I worked on developing was an infrared scanning sensor (bolometer), under contract to Intelsat. I don't know whether they ever ended up using that particular design or not; I had moved on to other adventures by the time it would have flown, and the processing technology available rad-hard had advanced quite a bit by then.
I'm rather pleased to admit that I was part of the team that designed and supplied the torquers for the Hubble Telescope, and one of my joys is when someone asks me what I did in those days, I pull out a pic of the Hubble and point to the diagonally mounted torquers. I helped with a lot of great projects in those days; it was a lot of fun, and of course very instructive in the importance of doing things correctly.
> The real question is should humans mess with the earth sun energy balance at all.
They're insane. They have no concept or appreciation of the scale of the forces they're dealing with, the history of Earth's temperature over the last, say, 400M years, or even the most recent 50K years.
They make foolish assumptions of stability and continuity which are not supported by the geologic evidence, much less things like orbital changes, solar variations, etc. They are the most dangerous kind of fools.
I'm 72 and likely won't live to see such things attempted, but I fear for my daughter's generation and onward. They will bear the brunt of the crazy, murderous antics of these so-called scientists.
Unfortunately these science types are not insane they are evil. With the right mega engineering man could affect the earth system. The evil ones only care for money and their political masters are all too happy to feed them money as long as they tow the line of the Marxist ideology. A one or two percent loss of solar influx wouldn’t be catastrophic it’s window dressing on a power play. If they went for ten percent or more then the whole planet would be in danger. Fortunately a solar sail of that size is outside of human tech for the time being if ever balancing a sail size against solar wind is not going to be easy. The other way is stratospheric particulates, sulfur dioxide , micro carbon blacks or sodium would do the job put it in jet exhausts as a fuel additive there is enough high altitude flights per year to put enough particulates up to cool the planet by tens if not twenty degrees F . 50,000+ flights per year fly in the upper atmosphere change the jet fuel change the world.