M H Stein wrote:
  Why the "but"? Did I imply anything of the
sort? Did I say that a
 carpenter should know how to make an electric saw or even repair
 it when it would be a more efficient use of his time and skills to just
 take it to a shop or buy a new one?
 ------ 
But it does help if knows how to change the blade. :)
Same with hardware/software -- know your tools.