Everybody is built differently so if you bench flat backed and don't set yourself up for a proper bench, sure you can touch your chest no problem. Some people can do it easily, I can't do it at all. When properly setup with my shoulders back and scapula withdrawn to suppoer my spine and expand my chest, my body stops itself at 3" or so off my chest. It won't go past that point no matter what. It's how I was told to properly bench have been shown this method and trained in it for quite some time injury free and have made great gains in it. Now like I said, everyone is different. FIRST learn proper benching form and mechanics with lighter weight. Your body will tell you where it's supposed to stop. Don't listen to the whole mindset that everyone is the same and it should all be done a certain way. Bench the way YOU bench and the way your body allows and you'll be fine. There are guidelines but this isn't the ten commandments. Nothing is set in stone. It's just there to give you a starting point. Now I don't know about the whole 20-30lbs more if you don't touch your chest but, if you're one of those people that only go to 90* to where your upper arms and elbow only go til they're parallel to the ground sure that's feasable but, I wouldn't recommend benching this way unless you've had a past injury or experience pain going beyond that. If you just bench that way to bench and holler out big gains, you're cheating yourself.
