Sometimes, it is not just a matter of sharpening the blades assembled or disassembled. Often, if you close the pruners and look up at a light between the two blades, if you see light, that means that the pruning blades are "warped" , usually happens after cutting a thick cane or two, which results in a warping of the blades and no amount of sharpening can correct same. The test to check your pruners after any method of sharpening, is with a simple piece of white paper from a printer or typewtriter. It either cuts or it doesn't. If the latter, don't torture yourself, turf them. I must have about twenty pairs in the basement, let alone the ones I "discover" every Spring when weeding! LOL.
