I don´t now much about clarinet but what you mention is pretty much standard in all fields of training. From my personal experience with learning instruments my teacher for violin asked me to do so and my teacher for drumset asks me to do so. My daughters teacher for cello also uses this type of exercise from time to time.
Regarding the clarinet: E.g. Keith Stein in "The Art of Clarinet Playing" says that training with the "Schottische Figure" (that is dotted 1/8 with 1/16) trains uniformity of note length and maintenance of breath and embouchure.
My 2 cents: I don´t see that the type of instrument plays a crucial role for this type of exercise. Of course, when applied on piano you won´t train maintenance of breath but the basic principle is the same:
In cognitive sciences these approaches are named, to my knowledge, de-accentuation or desynchronisation. And they deal with two effects: To perform a periodic task you will have to continuously manage phase correction and period correction. Phase corrections is not cognitively controlled, while period correction is.
With de-accentuation you remove the focus on period correction and you can use the limited resources of the brain to focus on other aspects.
As a professional trainer I see two other advantages: 1. breaking routine can support interest. 2. breaking routine can tackle frustrations and frictions coming from repeating a routine too often without rewarding progress.