Actually I disagree completely. Heavy weight low rep has proven time and time again to be a mass building form of training. High reps, not so much.
Winny is used pre comp to remove water from your body and give a dry appearance, it's not really going to add much size.
Anavar (var) is great for strength, won't aromatize, easier on liver, bad on lipids. You can add mass from Anavar (var) but they are lean mass gains.
Many times with things like tren ace or Anavar (var) , your body is losing fat but gaining muscle so you might not see much change on the scale, which is really not very important, but you will see your body change pretty rapidly and you will look bigger and better because you are lower in bf but also maintaining and adding muscle.
If you are not growing or gaining like you want to, its your diet or your training. If you want to add size, increase calories and protien. You have to provide nutrients to grow, so no matter what, more food = more size.
Heavy low rep training is great for adding mass, but also when cutting. It builds muscle with proper nutrition, and builds strength. Doing high reps may give you a good pump and cardio workout but how are you really going to gain any size? 10-20 reps is pointless to me. 6 and under is where it's at.
For guys who already have the size they want, more reps is fine to maintain and take some stress off their joints. Bodybuilders have bodybuilding diets, powerlifters have powerlifting diets. Most PL aren't looking for a six pack, they simply want strength, so carbs, fats, protiens are all good for that. BB who step on stage, or are in a magazine most often don't look anything like that the rest of the year, most look more like pl's.
Times have changed and with the addition of lots of good horrors and gh, along with genetics, more and more of the top guys stay pretty close to contest ready most of the year. They may not be single digit bf all the time but it will be close like 9-11%. It benefits them to be ready for guest posing, sponsors, magazines, etc to be constantly pulling in the cash. No one wants to see a top BB looking fat but in reality, when it's time to do some serious bulking, some do have to add bf as well to gain the size they want and need to progress. That doesn't mean they have to get sloppy, but for many people it's very difficult to get to or stay in the single digit bf.
And they aren't doing this by doing a hundred reps an exercise. Everyone is slightly different, but look at yourself or the people in your gym. You will see the guys who train 5 days a week year after year and always look the same. I bet anything they are doing some higher rep training.
In all reality, you could only do 3 lifts, and gain size but most people throw in a few extras. Deadlifts, squats, and flat bench will work every muscle you have. You could skip arms, abs, and still grow. It's ok to do a little abs and to hit a few sets with arms but there is no real need for dedicating full days to them. You work your bi's doing other exercises and tri's on days like chest day.
5x5 or something similar will not only add strength but mass. The difference is, if you want to grow you need to eat to grow. If you want to cut and lean out, you adjust your diet to cut which usually means adding some gear to maintain muscle and going in a calorie deficit to drop bf.
Test, deca,tren are all that's really needed for anything you want to accomplish. Orals can be a quick way to big gains but hard to hold for most because they are adding to much water.
Just find what works for you.