MM you are absolutely right. Airlines are not comfortable with new hires having too much of a light-aircraft background, or who have the instructor mentality too much ingrained. It can take too long to erase the old and replace with the new program (if you'll excuse the computer analogy), and time is something airlines don't have to any great degree. If they're recruiting, it's because the job needed filling yesterday!
It might seem unfair, but the jobs always go to those who have the right qualifications and are in contact on the day the job becomes available. 24 hours earlier or later and you're out of contention. Have the wrong CV and you miss out. That said, what doesn't suit one airline (or Chief Pilot) may be ideal for another. You just can't get past the fact that there's a lot of luck involved - as there is in any desirable career.
Scroggs