Oops--I think I may have jumped the gun--XYZware had a function that I had not yet explored, and so you actually can engage the slicer with no printer attached to your system. In fairness to XYZprinting, I thought I would follow up on this, in case somebody else were to stumble across this and get the wrong idea.

When no printer is connected, the Print box is greyed out, but there is an EXPORT button. Pressing that will bring up the same dialogue box you get through the Print function, but instead of sending the G-code to a printer, it allows you to save it in their proprietary .3W format, where you can load it later for printing. The good news is that you get the same slice preview that you get in the printing process, without needing a printer attached.

That having been said, I have downloaded Slic3r and have started playing around with it. I figure it is a good idea to diversify in terms of my toolset.