Tom:
There are several GCA regulars who know pretty well the work on the South course at Olympia Fields; let's hope they chime in. My sense is that the Bendelow original was largely restored, although a couple of holes from what I heard were significantly changed. The North course was also restored prior to the Open, but I think Mungeam's work there was more along the restoration vein.
I think Beverly fits the "restoration" definition more clearly than Flossmoor, which has one brand-new hole (par 3 13th), an essentially brand-new hole (the 8th), and two quite significantly changed holes (4th, short par 4 on the front nine, and a par 4 on the back nine -- 12?). I agree it's something of a slippery slope definition.
I think Forse's work at Lawsonia bears mentioning; he clearly worked at getting back to Langford's original intent there with wide fairways and large greens. It could still use a bit more restoration, but it's siginficantly improved. Tom -- join us for the Midwest Mashie in May of next year to see it up close!