IF one is ever concerned about a pilot not handling engines correctly, or not having both up to the flight gate, a handy solution is any time the collective is moved, or being moved, engines matching has to be front and center. Gives one the opportunity to recognize a frozen engine, a frozen engine that is causing the other engine to respond in an unanticipated fashion, a lagging engine, etc. etc.
Years ago a bright BH212 Captain on the Brent lowered the collective lever to note the Nr going down - clever fellow undid what he did last, which was lower the lever shortly followed by raising the lever and restoration of the Nr, then correctly identified the problem and shut down the affected engine. One wants to catch those problems fast, before they become big ones. That incident could have been a ditching. Sounds brain dead but it isn't for some!