Thanks for your post.I have been running 190s and the bike handles IMHO better, It turns in easier and is easier to manage. I have gone through dozens of tires on my H2 and have even tried to go back to the 200s just to see if I could feel the difference. There is a difference.
As you seem to have a good technical knowledge of this field.There is a good reason the H2r has 190's and it's due to 'lean off knee down' which is done in racing to keep the bike more upright to give maximum grip but most street riders don't do this so the tire is wider (and heavier) to give more grip. There are also changes in the radius of the wheel which is less pronounced the narrower the tire. There are more complex issues at hand but this is basically why high performance street bike tires differ from the track models.
Thanks very much ! I never would have thought of that !You can't ride the H2 to it's full potential on the average road for very long and track riding style (knee down) will eventually involve a broken leg so having more rubber is more practicable even though the un-sprung weight is more. The 200 tire is not there for looks unlike some bikes only have but to get the best out of street riding for the H2. If you hang off your bike street riding (dangerous) then you could use the 190 as you don't need the extra rubber (bike stays more upright) although you won't get the change in road contact circumference (RPM variance) you would with a 200. Draw a circle representing your tire, measure the distance around the tire which represents riding upright, now draw inside smaller and smaller circles which represents lean angle and measure them, see how the engine RPM changes due to final gearing (tire) and the rear wheel take a slightly different track depending on that contact circumference.
Do what makes you enjoy the bike, tire width does matter.