Thanks to everyone who commented yesterday.  Alfred, yes, I too wish someone had said this to me way back. There were many aspects of my career that were accidental.  I don't regret where I am and, like you, I am happy with what I am doing.  I think I may have been able to get here sooner, though, if I had been a little more focused.

Some exciting possibilities have opened up.  Exactly how feasible are they?  It's difficult to say at this point.  But I would really like to pursue them until such time as I know for certain that they are impossible.