The tiny leaf debris were difficult to remove with a leaf net because it was finding it's way through and making the water cloudy. There was enough of it that vacuuming to waste was warranted. I think 1/4th suction power would have worked fine to remove what I was vacuuming, this was much easier to vacuum than the dust that turns to dirt in the pool. I shouldn't have referred to this as "dirt" in my previous post. Recirculating would have caused cloudier water. A couple times when I vacuumed too long, I could lift the vacuum head and debris and cloudy water would come out. When I went to skimmer end, the same was true, and the pump basket was cloudy and wasn't clearing after detaching the hose, and the return jet was barely trickling out with cloudy water. At some point before this near complete loss of flow, the debris were still getting sucked up until the water finally stopped flowing. I would say that's evidence that the debris I was picking up required very little flow to get sucked into the hose.
Thank you both for your opinions and suggestions, it helped me decide on using an adjustable valve instead of guessing about how much and how small of piping and I will remember the suggestions presented and use them when I feel they are the best option. The sock could have saved me some backwashes, but I think I would still have chosen to vacuum to waste due to the amount of debris if it didn't use so much water.
Has anyone ever tried using low speed on a 2 speed pump when vacuuming leaf debris to waste to save water?