Fair play,fella,no such thing as "fully" qualified
I was lucky to have a mates grandad,start me off,with the plumbing staples...wiping joints,soldering,principles of hydro dynamics,including one i have used loads - gravity systems.
I fitted my first solid fuel back boiler,at fifteen years old
and have just purchased me second Surefire2,and done a rake of pipe work on me own house.
The interesting fact,about plumbers,is that they were required at one time,to do ALL lead work. So lead burning (welding) chimney aprons,valleys,flashing,etc,were all part of the trade.
You sure appreciate the ease of use,of Fischer fixings and modern adhesives,if you have ever done vertical lead sidings,fixed with masonry dovetails,using lead-dots.
I would say the greatest benefit,of learning the ways of a new trade,is knowing if an individual purporting to be a professional in that trade,is on top of his job.
It also means you gain a fresh and deserved respect,for those who are good at their trade.
I have posted this one before,but here it is again...
I was on a job years back,where this "plumber" was installing a complete heating system,in a property being refurbed and extended.
There were pipes running everywhere when we landed,and i extended the hand of friendship,introduced meself,by saying "so,you
must be the plumber?...."
The dude had a proper fit...."I'm not a plumber...mate...I'm a heating engineer...." Real upset...spent the nest week sulking and practising his frosty look...
He started filling the system,and oh dear...it was like the evacuation scene,in Alien...like the wetting jets,on a dry-ski slope...all over the place...
I seen his desperate,futile panicking,and chose the opportunity to deliver this line..."What you need my friend,is a plumber!"