Hi Kilty,
I speak as an utter tiling novice.
I only did the months course but had loads of practice getting it wrong before that

, but one thing I did learn, was that preparation and planning are the keys, whether in this job or in my former profession.
The law of P's spring to mind - P*ss,poor,planning,promotes,p*ss, poor, performance
Preparation and planning are vital in all jobs.
There are so many areas in tiling that need care and attention, but not setting out correctly and getting the datum line out by a gnats scrotum will be evident far before the tiles start dropping off the wall because you failed to prime correctly, etc (not that you would of course)
Carry on doing what you are doing and there will be no comebacks.
But let others more skilled in tiling advise you better.
frogeye (the dust sensitive ex-
tiler 
)