Yes, that would be correct. If there is agreement there is no need to take it to court in the first place.
Just be darn sure you know how your state defines "life support." In Florida it is defined as "food and water" as well. And also, you may want to discuss scenarios rather than saying "Nope don't want do be on a ventilator at any time" My father had a surgery for intestinal blockage and was on a ventilator for 1 1/2 weeks due to his blood pressure not being stable among other things.
Thanks for the info. The whole life support thing is such a gray area.