Interesting pic Doug,
I couldn't agree more Alan, IMO the worse thing they ever did was give carpenters nail-guns.
I've injured myself I don't know how many times up in roof voids, on nails protruding from places they should never have been in.
I've also noticed that them nails used in nail-guns are twice as sharp at the point as standard (manually-fitted
Good for tearing into your hand in a dimly-lit roof.
One thing I have learned, is never sit down on any trusses or wall plates in a roof in New Zealand.