Well Six, I admit I am astounded. I have been tilling with a Cub Cadet 8 HP 2pt tiller for several seasons, and the rocks were really beating it up. It is so light it bounces badly and I am concerned about shaking it to pieces, not to mention tine wear. Of course, these are small tines with shallow bite. But it exposes rocks well. I can see how a big tiller might powder up the ground and allow me to bury rocks- I mean, if you've done it, there's no way to argue with that. And I do have an 8 foot cultipacker with a big weight I usually don't even need. But I suspect I have too little soil to bury the rocks. I mean, when I am done tilling it looks like I was digging potatoes! I understand that most food plot crops grow very shallow (except for those new radishes) but I can't visualize it working for me. And then there those rocks are, sitting on top just begging to be removed. Some way. Now, a real rotary rock picker would do it for sure, tilling or no tilling, but I have never seen one in my area, much less for rent. On the other hand, I'm no farmer, so why would I? I'll just have to look.
I don't want to hijack the thread so I'll just let it go with the general conclusion that heavy is better if you can lift it, and if not, go with special compact rakes. But I can't get that image of the round-tine rake out of my head. Too bad I don't weld. A 3 foot prototype would probably answer the question. Say 1/4-3/8 diameter teeth, about 10 inches long, only slightly curved, maybe spring loaded? Yes it would fill up fast but I bet it would collect those rocks!
Dragoneggs, I bet the rake will work great for what you want to do next. From those videos it looks like they dress ground pretty nice. They should probably call them "ground rakes" or something instead of rock rakes. As other threads point out, I bet of the flat tines were replaced with healthy thick round spring tines, like overgrown dethatchers, that would actually work on rocks.