bill- the contents of a can and the depth of an ocean are not the same as dating methods since the former are measurable in the present,but dating relates to the past,and as i understand it involves assumptions which are not verifiable.
and if they can get the date of rock formation of known age wrong,why should we trust the method for rocks of unknown age.
as to an exact definition and technical applications,i leave that to you.i deliberately said "some sort of..."precisely because i expected you to call me on it.   my point is that instead of some clear explanation that proves darwinism to be true,i am just assured it is true.which is just what i am accused of doing because i believe the bible.