Its something I have always felt would be highly beneficial. Other features and clamps can be in the way, and planning around that is always a pain. A dummy operation between operations is an option, as is adding individual instructions in operation headers and footers, but its slow, clunky, and has to be done for every operation. For a complex one off job the time spent manually taking those steps is daunting.
I haven't got my mind quite wrapped around it yet, but how about doing something in the post processor. In the post processor footer and header. You could easily duplicate your post processor, so you could only use that option when you need it, and it would only work when the operations are discrete. It would still not work for something like pocketing or profiling multiple items in a single operation, but it might work for nesting where it generates multiple discrete operations.
You know the more I think about it the more I realize even if you can do it within the architecture of the post processor there will be issues. Oh, well. Maybe it will interest somebody smarter than me.