I think I figured out what they are trying to tell me.
10 lbs grain 10 gallon batch 1 quart per lb= 2.5 mash 8.8 sparge
This is the mistake they're making, in my opinion. I recommend upping the qts/# with smaller grain bills. Generally, I add enough water to the mash to get half my volume from first runnings after absorption.
For example, for 10# in a 10 gallon batch, assuming 1.2 gallons absorbed and 1 gallon boiled off:
6.7 gallons mash water, for 2.68 qt/#.
5.5. gallons sparge water.
If the 2.68 qt/# makes you nervous, then mash in with 5 gallons, for 2 qt/# and add the remaining 1.7 gallons as a mashout or to the sparge.