It works ok although I modified it, more volume in legs/back from what I can remember, and I made it 6 days not 3. Full body workouts in under an hour with sufficient volume only 3 days a week is not possible for me, I'm in the gym 5-7 hours a week and I do not do high volume.
The rest periods have to be extremely short to make that happen, and that gets into circuit training which is not going to be the best mass building program at all. If you follow HST to the letter though, you will sweat plenty because you are working out damn near non-stop, which is not optimal for building.