Totally not trying to contradict you though Glen, you're the profesional; any new riders please listen to Glen.
But personally I use the outside two and get easily stand it up without hurting my hand.
I use the inside two mountain biking so I can hold on to the bars, but on the moto I find it nicer using the outside. Maybe I've gotten used to using them for 'force' holding on to the pushy?
I love being technical though, and technicaly, outside fingers have a firmer grip though it's hard to tell. Do the "crush your friends arm" test if you don't beleive me, haha.
providing some drag thus keeping the back in line when your braking hard in a straight line or pulling it in when your cornering.
None of my riding instructors ever told me that, unless I missed it. Just after getting my L's a mid-30's guy on a GSXR told me to never use both brakes together, he said it's a death wish... use all front or all rear, and avoid using the front at all costs. Didn't sound right to me so I ignored it. But that's a worry ay.
Is stuff like that set in a syllabus or are instructors allowed to chuck a few of their own points in?