The 0562 is one of my favorite knives. As others have said, the "thumb studs" are stop pins. ZT specifically made them round/domed so that people don't try to use them as thumb studs.
The problem with knives that are thumb stub and flippers is that the detent can't be dialed in for both. The optimal amount of force required for the detent is different when using different opening methods.
I like the design of the external stop pin located on the blade itself. Once the knife is locked open, the fact that the stop pins are on both sides of the blade means that there is resistance to lateral forces, such as when prying. I know that knives aren't for prying, and I always carry a multitool with me so I never use my knives that way, but if you need to, it's there. Hinderer and Strider both use this design. And if look closely, you'll notice that the G10 or CF show scale are cut so that they are slightly recessed at the point where the stop pin hits so that it contacts the steel liner. Good design all around.
It's called a slicer grind because that's what Hinderer calls the style. Its slicier than the Spanto that the XM-18 originally came with.
I've spine wacked my knife pretty hard, and it won't close. If I really needed to keep it locked down, I can induce a little bit of lock stick by pushing the lockbar further in from about 30% normally to about 50% lockup. At that point, it will stick, and it's definitely not going to fail a spine wack test.
I like tinkering with my knives, and I recommend using teflon/painters tape. Wrap it on, maybe 5 times around or so, and you're good to go. Just make sure you wrap it in a way that it doesn't unspool when screwing the pivot in. I'm too impatient to wait for the loctite to cure.
And I heard this thread needed pics... here's my modified 0562CF. If you like modifying, this is a great one to do it on.