A guy recently described a somewhat frightening event involving a panel raising bit in a router table. Somehow, while running a panel "something caught," causing a violent kickback and bending the bit's 1/2" shank. Fortunately, the guy was not injured but he was asking "if anyone else had a similar experience."
Large router bits like this are pretty common these days and I even know of some production shops that run these bits in router tables. The problem is that panel raising router bits take as big a bite as any full-sized shaper cutters. But the stress this puts on a 1/2" shank is far beyond what I consider to be safe.
When I set up my first "real" shop, I bought a small shaper with a 1/2" spindle. I mostly used it for making smallish moldings. But the day soon arrived when I needed to make raised panels. I got a cutter with a 3/4" bore and bushed it down to run on my 1/2" spindle. And like the guy with the question, I had something catch. The resulting kick bent the 1/2" shaper spindle badly enough that the cutter gouged a big half moon in the C.I. top of the shaper. I also got a very fine and rather large and ugly bruise on my thigh.
The next day I bought a shaper with a 1-1/4" spindle (and, needless to say, a new cutter!). Of course, back then I was young and foolish. Now I'm old and foolish but I still run my panel raisers on big spindles! I still have occasion to run large bits in routers but I am never quite comfortable with having that much steel spinning that fast on a 1/2" shank.