ICE is just expensive WATER (I get all I want for free at the lot where I park my rig)
ICE does not have scrubbing properties (Agreed, but it seems to dislodge heavier deposits at the bottom and the upper sides of the tank)
Use a high water to solids ratio when flushing toilet (Agreed - MANDATORY)
Dump when tank is 3/4 or higher level
add water back to tank so it does NOT dry out...stuff can't stick and get hard when kept wet. (Agreed, the melted ice always provides the "starter" liquid that keeps the tank from drying out)
ICE is for drinks not waste tank (I don't drink, and I never use ice for beverages. It's usually where I put my fish):)