That's where Heatercraft says to plumb. For mine, I plumbed at the intake (It's a T with my Heater). For Cold, I followed Heatercraft's example and T'd into my raw water intake as shown. in the OP's pic.
I have excellent flow and couldn't imagine needing more. The hot is very hot. So much so, that I only have the Hot knob about 1/2 and Cold Full.
If one day you're asked:
" How did you spend your time here on Earth?"
Will you say:
"I kept a crabgrass free lawn"
It's time to SKI.