I think everyone can tell that the growth was due to the fertilisers.
Ah... then what was the question again?
Fertilizer lead to more growth and larger leaves. How about not applying fertilizer? It's just a thought, maybe you disagree.
Defoliation does NOT lead to leaf size reduction - at least, not directly. Ramification does - more leafs, smaller ones.
So, you need more ramification - and thus, you should NOT defoliate again, you should let things grow so you get more branches, secondary branches, tertiary branches...
Defoliation is only done on established trees. Your tree is still in training / being shaped and you should not have defoliated.