Psychopath, I have a clue for you, the basic human body 101:
It's the cartilage (connective tissue), between the rib bones, that expands due to the internal pressure put on it through the deep heavy breathing & pullover stretches (external pressure). Cartilage begins to harden between the ages of 23 to 26, and loses it state of flux/flexibility as when the body is younger. After 24-25 (the mean averages) it will be difficult to expand the rib box. So it's quite possible to add 2 to 3 inches to the chest, with serious attention to breathing squats and pullover combo's, and at a younger age. So if your chest measures 44", getting to a 47" inch chest would be quite rewarding, I would think, to the average BB'er. And not in that long a period of time.
Breathing squats & pullovers also tap the metabolism to preform at a higher level, which in return, can increase whole body muscle mass. Squats can be considered a growing exercise. Breathing squats will also increase the cardio and stamina (endurance + strength) factor. I found it great for getting into football shape, during off season.
I put a few older men (ages 53-64) on this program...Starting very slowly with just the bar at first...increasing the weigh every week on the 20 rep squats (no, not around 20 reps, but the full 20 reps every set...if working with me, you will actually be working), with surprising good results. Seems to lift the muscle attachments/inserts, giving a fuller and lifting affect to the chest. Good Luck.