Lets say you have a large collection of slides, subsets of which are suitable for different audiences, say. And you want to be able to print these subsets easily.
Creating a “custom slide show” is easy enough and makes sense, but if you want to print, you seem to have to figure out the numbers of the slides you want each time and enter them manually or manually go through show/hide every time you change.
Seems like it would be easier if you could just select which custom slide show you want to print.