Kent - Yes, precisely.
Jitter is timing errors which were believed by many to exist beyond human hearing, because when translated into the frequency / tonal domain, the artifacts are beyond the audible range. The auditory brain must work hard to weed out the temporal artifacts of jitter, causing fatigue or other distancing mechanisms. Dither spreads them toward randomness and therefore more easily ignored.
In higher order slopes, the onset transient arrives in distinctly parsed segments, one for each driver. The ABrain does indeed combine them, using memory, later-arrived reflections and decay parameters to make sense of them - all occurring later in time after brain work. Live music comes all intact. Well recorded and made music played back through single speaker / headphones can preserve that all-intactness. Multi driver / higher order slope speakers cannot preserve it; although they minimize the deleterious effects by creating timing with few or no sharp discontinuities, saying the ear can't tell the difference between single or multiple arrival times. In a manner of thinking, they are of course correct - the ABrain is very skilled - unless you are a listener who appreciates the coherent rightness of unified arrival transients such as heard in real (non-reproduced) music and sound.
That particular component of "realness" appreciation is shared among many Thiel owners.