Tire feedback when cornering So I bought a Continental Der Kaiser (similar to this one) and the peripheral knobs are pure magic. When I shift my weight slightly to the side, the central thread disengages and the peripheral engages. This has two advantages:

The grip is excellent, the bike feels as if it is upright, while it is actually 45 degrees tilted
I can very cleanly feel when the switch happens, so I know how hard am I cornering and what is the actual friction with the trail.

I have had similar experience (without the first advantage, only the second) with much cheaper tires, similar to the following, but with uninterrupted central thread:

The side knobs change the feel of the bike while cornering, and I know how close am I to losing traction. The effect is most pronounced on asphalt.
However, my new Scwalbe Land Cruiser tires have a round profile. Lacking the peripheral knobs, I feel very insecure during turns, because although the tires grip well, the two times I fell there was no warning - just the tire sliding our from under me. A tire with peripheral grips would have stood on its peripheral knobs and I would have felt that the edge of the tire was getting at funny angle and would have straightened the bike.
Is it true that round profile tires (like the Land Cruiser) are inferior at cornering (on pavement)? If so, what are their advantages (considering that side knobs do not add to rolling resistance, when travelling at straight line)?
As a bonus question, is the technique for cornering with round tires different from tires with side knobs?
Knobs and pavement don't go together. At all. Knobs are made to dig into loose riding surfaces to optimize traction. They can't do that on pavement and, among other reasons, that's why road tires don't have knobs. 

What you're likely feeling with the higher profile knob is more warning before the tire cuts loose. The lower profile knobs on the Land Cruiser almost certainly grip pavement better, but offer less warning before they let loose.

The best tire for grip on pavement is a slick. Slicks offer the most rubber in contact with the pavement and the least deformation under side load. The flip side to that coin is that when they're ready to cut loose they offer virtually no warning, and when they're gone they're gone- your chances of recovering traction are nearly zero.

To kind of answer your bonus question, cornering techniques don't differ so much by tire, but by riding type. There are differing cornering techniques for road vs mountain bike riding. I would say that cornering on dirt is much more dynamic than on pavement.

EDIT: in response to your question in the comments:


  So basically my question was "[Your third paragraph] - is that normal?" and the answer is "Yup, deal with it."?


In terms of your tire cutting loose, the answer is partially yes, but not entirely. Proper cornering technique and weighting of your bike, especially your front tire, will help you maintain traction. Keep in mind that it's different for road than it is for mountain, but that's a different question.

A set of tires specifically designed for pavement would make a huge difference. You're not limited to narrow road slicks either. The Specialized Electrak is very wide for a slick, and Schwalbe has several very wide mostly slick tires that can be run at very low pressures (as in, 20-30psi) which equals a lot of rubber on the road and a lot of traction.

In the end though, when you lose the front end on the road it is going to be harder to recover for a variety of reasons. It's not the same as temporarily losing traction in the dirt because you hit an especially loose corner. Traction on the pavement is typically pretty consistent, and you're usually going significantly faster, so when the front tire lets go, it will be very hard to regain traction and stand the bike back up. The tips above will help with the problem but not eliminate it.