When riding conditions favour, and you know what you are doing, gear changing without a clutch is easy.
It is a matter of knowing at what time to change and where to have the throttle, I guess I may have an advantage here cos I use a twister.
But get it wrong, especially when changing down to a lower gear, you put extreme forces on the gear components, and you are more than likely to break something.
It is not just a matter of stabbing it into gear, it is more a case of feeling where the gears are.
For those who wish to learn shifting without the clutch, may I say, try it by shifting up through 4,5,6 as forces on the components are lesser.
Do not even dream of downshifting, until you have mastered shifting up through the lower gears, as downshifting is a whole different kettle of fish.
It is an aquired art, and not everyone can master it, if you continually crunch gears or have to put more than a little pressure on the gear lever, stop trying and use the clutch.