[hellosailor]

Rockter, when Stu says "Never" that's because sooner or later, most folks will have an accident leaving the water pressure ON when the engine is OFF. In your case you are manually ensuring that the water pressure is OFF except while the engine is running. That's great, as long as you never make a mistake or get interrupted.

What Stu says is safer. If folks do it his way, they simply can't have the accident that you can. That's just called good engineering, i.e. setting up things and procedures that guarantee an accident can't happen.