Mark Six...
I would have said it a bit differently....after 2000 hours of Chinook flying in the military...I thought I knew how to fly helicopters. In short order....after becoming a civvie helicopter pilot....I discovered there is a whole new world out there.
Longline work and military underslung work are two very completely different skill sets.....and not to be confused in any way as being similar when it comes to "underslung work".
If you cannot see the hook and load.....and do it all by yourself....it is not long lining.....sorry.