This is a case of someone reading boards and using "recommended dosages" they see all over the place. Without any prior experience on their own bodies. This is why some of us say that 300mg of Equ (or equivalent) is enough for first timers. I've done over 10 cycles and never used as much gear as this guys using in his first as my body simply doesn't require it to grow. Saved me lots of money and sides over the years as well as it being far easier to hold onto those gains.
It sounds like you are pretty sensitive and respond well to drugs. You probably could have achieved your goals off the anavar dosage alone. Strechies are permanent but will fade with time.