Official faster-draining concept, safe comparison instructions, and a clear missing-cost/effect warning.
The official description confirms upgrades can make draining faster; compare only the rates you enter and keep missing costs or effects labelled unknown. A source-bounded upgrade guide with player-input rate comparison and no unsupported cost/effect table.
For +1 Drain Water Per Click upgrades, compare two water-per-click rates and keep missing costs or effects out of the arithmetic until a current source lists them.