I don't know about handguns but I knew a guy who poured so much oil into his M1 rifle that when he fired it some spattered into his eyes. That may be a good argument for wearing eye protection, but it is also an argument for not overdoing the lubrication.
The fact is that handguns don't need much lubrication. With revolvers, a few drops in critical places is plenty. With auto pistols, a few drops of oil and a small amount of grease on the rails is plenty, and even grease is not necessary unless the gun is being subjected to long term firing. Otherwise, a good gun oil will do for the rails as well as the lockwork.
One problem with over-lubing is that oil in the chamber will increase the pressure on the breech face (since the case will not adhere to the chamber walls) and that will eventually harm the gun.
Jim