IMHO, a hollow ground edge requires less honing after the grinder has done the shaping. When you lay the bevel edge on the water stone (or sandpaper), only the tip and 'heel' of the hollow grind contact the stone. Thus less material needs to be removed during honing. What you end up with, then, is still a 'flat' edge at the proper angle at the very tip of the tool, not a 'curved' edge with too small an angle.

I do not return to the grinder for each sharpening. Only when I need to grind out a large knick, or when the hollow grind is almost gone. Otherwise, I just do the honing step.

That's been my experience, anyway. CB.