Element Profile by slope from element

ORD 2021R1 Update 1 (

I'm having an issue with element profiles, in this case projecting to the offside edge of a diverge nose (highlighted).

The mainline channel is profiled using 0% from the corridor element, its profile is on the left, and is as expected

The nose profile is created at -2.5% from the mainline channel using Profile By Slope From Element, but gives steps and bumps as can be seen on the left profile.

These irregularities are not present in the geometry, the superelevation, the profiles of the corridor elements, or the duplicate element of the mainline channel, so where are they coming from and how can I remove them?