Why do you only allow 3 isolines for the default “Factors of 2” isoline preference?
This is done to encourage proper template usage. Only two lines are generally needed, one at the target minimum and another at half this value. A third line at one-fourth the target minimum can be useful in a rectilinear four-pole layout, but otherwise only contributes visual clutter. The “Specified” option allows as many as 7 isolines at whatever values the user desires.
