What I was trying to say, like you point out in the last sentence, you can get stronger and bigger and never experience soreness. It's not a pre-requisite for good training. It can hinder training if the soreness is bad enough to hamper your mobility and workouts. If I take a layoff from the gym I'm sore that first week or two back. After that I rarely if ever get sores but just like you I track my workouts so I know progress is being made.