It's how it was intended to be:
"by number of times contacted in the past, first" + "name, case insensitive, next" (to break the ties).
But it was really -- my mistake late in the 1.5 cycle -- and released now -- like this:
"name, case insensitive"
which is of course really really wrong.
Before the change for "case insensitive", it was:
"by number of times contacted in the past, first" + "name, case sensitive, next" (to break the ties).