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If you can tell me how to do that with a Phillips or a slotted screw driver, I am very much interested

Of course you can't. No doubt Robertson screws are great. However, all modern designs share the same doesn't-fall-off property, even the old Allen, with the added advantage that instead of four possible insertion angles, you get six, eight, or even twelve. If there hadn't been further advances in screw drive since P.L. Robertson, his design would be in common use everywhere. But even recently, Torx II is a big improvement over Torx.

In part, the Robertson screw didn't catch on in the US because after lengthy negotiations Henry Ford refused to license it for his cars. Re sizes of slotted screws: A pro is that slotted screw heads can be turned with almost anything, such as coins, knife blades, putty knives, tin can lids, and so on. The corresponding con is that non-commercial users rarely have a screw bit that actually fits the screw they are trying to turn. Moreover, the sides of the blade are often tapered, rather than parallel planes, with the thought that the bit can be wedged into a range of slot widths. But as a consequence of the wedge shape, the bit tends to cam out. Pro screwdrivers are sold that have exactly the right tip width for, say, the standard slot on #6 wood screws, and have parallel sides. A pleasure to use.

Notice that all the screws in a mechanical wristwatch are slotted. There is a reason for this. The original Phillips driver was designed for building aluminum aircraft. It was designed to cam out before the material being screwed into was damaged. Later cross-drive screws, e.g., frearson, were mostly not designed to cam out. As others have said, with cross-drive screw heads the bit is self-centering. It isn't with slotted screw heads, but the slot is easily restored. If you ruin a cross drive head you need a screw extractor. All the above are much inferior to Torx.

Sure it is. Imagine a clock that is gradually slowing down. Its rate of slowing down could be described in milliseconds per second.