We were chatting about this the other day.
I think it depends on the job as to whether contractors are better or not.
There's been 3 contract guys in a working flat with a big F'off shredder and chain saws, working their way up from Oxford clearing all of the offside over growth. They're doing a damn fine job and concentrating on doing just that.
If it were CRT doing the same job, how often would one of them be diverted off the job to attend to blocked overspill, clear debris from behind a gate etc? Often leaving the other guys standing around cos H&S won't let them carry on with just two of them.