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I believe heavyhanded (feel free to call bs heavyhanded) has done some playing with different cutting fluids and said using oil will give you a higher polish but simple green cuts faster and tend to agree...
I've never used Simple Green so cannot comment.
I've tried using no lube. The swarf and stone debris begin to clog the pores very quickly and need to be brushed off frequently. While it
feels like the stone is cutting faster its actually slowing down. A good example of this effect can be noticed with sandpaper sharpening - let the paper load up with debris and it
feels rougher. In reality its slowing down, clean off the paper and it feels smoother yet more steel comes off in less time. The grind troughs are cleaner cut as well = smaller burr formation. With a stone it works a bit differently, and a lot of accomplished folk use their vitreous stones dry, but for me it always works better if I wash the stone off periodically or just use some sort of liquid on the surface.
I used to use water and/or a mix of soap and water. This has the advantages of reduced clogging of the stone and (to me) improved tactile feedback. Its also easy to clean up and always nearby. I also noticed the stone needs to be scrubbed or lapped from time to time as it shows wear in high use areas and reduced grinding speed - similar to dry but with more up time. In a pinch, water works but I find it helps to rub the stone with a fingertip to loosen the garbage prior to adding more water/soap. When I do machetes or hatchets I use water and dunk the stone often. You'd be surprised how much stuff winds up in the bottom of the wash basin - steel
and stone.
I switched to oil after noticing a few advantages. Oil actually floats the swarf, so the surface of the stone cuts cleaner and stays in good shape after many many uses - this is huge. In fact if you wipe the oil off before it can soak in, the stone stays practically like-new indefinitely. I also suspect but cannot verify that the oil helps break down the bonds in most vitreous stones exposing fresh abrasives at a much faster rate than water or dry. Downside is your stone wears a tiny bit faster and you need to watch it more closely for dishing. Upside is it grinds cleaner, faster and more reliably. Feedback is also (to me) a bit better than with water/soap. Lastly, by using an oil with some body to it combined with light pressure, the blade will "float" a little bit on the oil. This makes it a lot easier (for me) to get the softest possible consistent touch on the stone for finishing the edge. Many folks would be somewhat surprised at how fine an edge one can get from a humble combination stone. No doubt in my mind I get way better results using mineral oil. Other oils work too, but the mineral oil is cheap, easy to find, can hold a lot of swarf, can afford to loose viscosity a bit as it gets used and it'll still stay on the stone (maybe a teaspoon total will do for a full rebevelling and finishing), is non toxic, odor free, and washes out of your shirt a little easier than some other oils

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Experiment, have some fun. There's pluses and minuses to every method.