Millenium, true enough! Really HARD to get the crank at exact TDC and if you don't the piston will move to the bottom. The whole valve spring thing IS a pain in the butt, but it beats loosing a cam lobe!
I feel "paranoid" with the piston so far away from the valve. I guess I have "hope" that if it all goes to hell and I loose my air pressure I have a prayer of recovering the valve which stopped moving down into the cylinder because it hit the piston top. Could be "false hope" and your screwed either way!