Well now dirty boy, you also do not see Chubby guys stuffing 2.05 or 2.08 valves in a 305 engine. Their just is no room. Now could they notch the bore for valve clearance and shrouding? Of course.
Being as you are a "shrouding doubter" mebe you is needin to get copies of David Visard's books; How to Port and Flow Test Cylinder Heads and How to Build Horse Power. It may be an idea to also watch some of his PowerTec videos. You may just learn sumat before ignorance hurts you.
