I suppose the skill and experience of the recording mixing engineer can come into play if they know the defficiencies of the monitors themselves and compernsate accordingly in the mixdown but can we really count on this?It's all about skill and experience, all the time, period. Can we count on it? Er, we have no choice.
The recording/mastering engineer's tools (monitors, console, microphones, etc.) are the same thing for their art as the instrument for the instrumentalist. You could just as easily ask questions like "can a pianist ever get a light, delicate tone on a big Bosendorfer?" Or "can a flutist ever get quick, clean articulation on a heavy-wall Miramatsu?" Yes, there are some truly bad instruments out there, and some really amazing ones . . . but that's really not the point in the end.