I'm not sure how I got into this line of posts since I started a new thread but they seem to answer the question.

I have the impression cast iron is brittle. How brittle it is I am clueless.
I imagine the tub could get dropped a few inches in the described installations to get it to set on the rear ledger or in pulling out the installation 2x4 on the bottom. This small drop would not break it would it - or do I need to rope it or lever it down?

Has anyone done this installation on top of grouted down DITRA waterproofing and slip sheet - and not destroyed the grout and sheet?

For that matter is there a better way to water proof the floor under tiles and tub in a bathroom other than DITRA?