ORIGINAL: NM2K
I'm not trying to start a fight, T.O.M., but what you are describing is often caused by mixing Brand X 100:1 formula oil at ratios much lower than 100:1, such as 40:1. I've seen people bragging in print on the internet (no - not you) about giving their engines ''extra protection'' by over loading their engines with way too much oil. Then they ***** and complain that Brand X oil is garbage after using it incorrectly and loading their engines up with the glass hard deposits that you describe.
But it says right on the brand X bottle that you can mix their 100:1 oil at heavier ratios down to 50:1 on the chart. Guess they should remove that if it is only a 100:1 oil! Of course, their Dominator product is intended for 50:1 or heavier ratios.
I don't use the stuff but I have read the bottle.