..."a vast knowledge of motorcycles." ?? Well, you will certainly be welcome here where we never let knowledge get in the way of our opinions. :-D
In any case if you want to adjust idle don't mess with any screws. There is a black knob on the left side, behind and slightly below the left carb. Warm the bike up COMPLETELY and then turn the knob until the bike starts to falter. Stop. Reverse until it seems to be running smooth. Stop. Do it again. That should put you at about 1100-1200rpm. It is better to idle it a little fast than too slow, even tho the book says 1000. Your tach, even if you have one, won't be accurate enough to tell the diff anyway.
As you get miles on the bike and it starts to break in your idle speed will increase, so you will have to go through the drill again. I am talking about a STOCK bike here. If you have messed with it I have no advice.
Welcome to the coocoos nest.
Monte