Thought I may have done a bit of overkill when I bought a Camelbak three liter reservoir backpack. Maybe it will save time. Who knew a gallon of water weighs eight pounds?
The only place I'd consider carrying a gallon of water is when leaving Trail Camp.
The biggest mistake I made on my first Whitney Day Hike was carrying 8+ lbs of water/gatorade when I left the Portal. With all of the spots to refill/filter, there's no need for it! I don't like filtering on the trail, but I also tend to not take breaks as often as I should. If I need to filter every couple of hours, it ensures I'm taking the breaks I should, especially for others in my group that may not be as fit.