The course that I took, they coached us to use the back brake to “control your speed in a corner”…keep the throttle steady and use the rear brake to control the speed, then if there is any danger there is no lag when you apply the throttle…this was for our slow maneuvering figure 8 and tight left and right turns…but it could easily be translated to an on ramp, or corner where you need to scrub some speed off…
I would also use more rear brake than front in slippery situations…rain, sand, gravel, etc…spring riding conditions basically…fall too, I guess…
Where I live in Canada, the first ride is coming…the thaw is starting, but I still have four inches of rutted ice on my street…a few more days of this and I may be able to get out to the main street without dropping my bike…woo hoo…
Later.