Is that it and it doesn't harm the pump in any way ,but does the pump still switch off when you stop water flow or do you have to turn it of with controller
The Varistream will do it for you. That's what calibration does.
I ran a 3.8 liter per minute Shurflo with the first digital Varistream for 12 years without a pressure switch. It was on a Varistream analogue controller before that without the pressure switch connected. The reason why I purchased the Varistream is that it kept burning out microswitches.
The pump is still fully working in my old van which needs taking out before the van goes to scrap.
The only other controllers that also dead ends is the variants made by Spring.
Other cheap flow or speed controllers purchased on ebay and some suppliers do not have dead end abilities. They have to have a working pressure switch.