This is what is keeping me up at nights:

Larsen trusses have no stud cavity walls and in my building the trusses are also open to the rafter bays (i.e no top plates).

I assume it’s the resistance to the blow by the walls and plates of the cavity which enable the density. I will be blowing cellulose into spaces with no boundaries so how to do I get the density and how do I know I have reached it?

Is it all about feel (i.e. resistence to the hose) and sound (i.e. back pressure while blowing)?