Repetition counting, set counting and good form are all neccessary tools at given times to help get the most from your workouts - there is no doubt about that in my mind.
However, probably the most effective ''tool'' and training protocol is intensity - in my opinion almost everything else comes second place to this little gem. Without intensity what do you have? A workout which isn't taking your body beyond its comfort zone therefore the chances of changes occuring are quite small.
Studies tell us that muscular hypertrophy occurs when high threshold motor units are recruited leading to the stimulation of up to 10 times the amount of muscle fibres per repetition!! To do this you require intensity, with that said make sure there is literally nothing left in the tank from now on.