It works for me. Though I have no proof that its the best way. I would point out that it means my main mash is sitting there for extra time, so you want to be extra certain that your mash pH is correct, but I don't see any harm in mashing 90 min vs 60 if it is. Thats about how long it takes my sparge to heat up and about how long it takes to reduce the gallon (the extra 30 min that is)