With, or without a bypass hose a thermostat will still act as a thermostat and bring your temps up to where they need to be. It may open/close more often, or less often, but it’ll still do it’s job and give you the heat it needs.
I understand that however I didn't want to deadhead the electric pump. Already got it figured out after talking to Meziere by installing a t-stat with (2) 1/8" holes drilled in the flange.