Hi Jo,
I'm just thinking that it'd be more of a safety net to have full float when there may be extreme regrading in comp for a multitude of reasons, and then the shot goes through an even more extreme DI after that. I recently had an element created in TG that had to be re-started due to lack of detail in the blacks, even from an EXR. I had been told to make it extremely dark in certain areas, but then it just didn't quite hold up and looked a little crushed and flat in the shadows when toyed with. If it had been full float I'm sure I could have done something to bring out the detail in half an hour in a comp package, and not have to re-do a render on a very tough deadline job.
The DI is usually fine, but there are the occasional jobs that push what you've done to the limit, and it's only gonna get worse with studios pushing for more and more with less and less. At least with full float you can be more confident of elements holding up better, and less chance of a re-render.
It's doing the render anyway - why throw baby out with the bath water?
