This is one reason I mostly use Bridgepoint products. I'm not sure what is so complicated. I mostly use Bio Break or Flex powder w/Citrisolv. The directions clearly state how to mix them in a HF sprayer including what tip to use. I use a little 4 oz mixing cup because the Bio Break calls for 12 ounces and the Flex calls for 16 ounces in my 5 quart sprayer, both with the yellow metering tip. Flex mixes quite a bit easier than the BB but neither is a huge problem. Fill the sprayer halfway up (preferably warm water), add powder, cover the hole with one hand while you shake the container like crazy, finish filling with warm water, and give one final shake. I've done it this way probably thousands of times with very few issues that's why I continue to use the HF sprayer. It may not be the most consistent way to do it but it is consistent enough to be used on carpet and super convenient. Maybe the products he is using are not as good or consistent as Bridgepoint?
The Clean Machine