For many systems, performance can be significantly improved by educating the end users.
It might even be argued that training is required to achieve optimal system performance:
IIRC, Robert N. Bailey compares "handling software" with "shooting with a gun" in his book "Human Performance Engineering". Just as you need training to operate the gun properly (breathing, aiming, pulling trigger etc), you need training to perform well with software.
Practice/training is also one of the prerequisites of increased performance with keyboard short-cuts.
I also have experience myself with "domain complicated" desktop applications, where the end users really benefit from work-flow coursing and reviewing best practice.*
The question is, how can end user training be integrated into the UX plans without undermining the importance of the UX work in general?
I.e. avoiding situations where team members says "yeah, it is a bit complicated - but with some training it will be all right..."