Re: Pay grades
I can't speak for the spooks (apt it's almost Halloween) but other departments are on the DDaT payscale which allows them to pay significantly more for certain skills if you can actually evidence them, usually bumping the 'gurus' above their own line managers base pay.
It's still somewhat below what you could get as johnny freelancer, but it does help bridge the gap a bit. Only downside is it isnt pensionable and is a target rate which CDDO never bloody change, so each year it gets eroded by your base pay increasing, increasing your pensionable earnings and therefore reducing your take home pay.