Rod Caps, balance, weight confusion. Need help

This is how I've been told rods are manufactured. First forged rods.
Take a hunk of metal and heat it red hot and hammer it into a shape on a big press usually between more than one set of dies. Then the rod gets machined for the thickness and small end .the big end is drilled for bolts then cut in half then bolted together and finish machined.
Do you see now why each cap must be kept with its original beam?
Powdered metal rods the cap is cracked off making them even more unique to their matching beam.