This is a weak argument red.
To answer your question, no I have not ever been a package driver. Have you ever audited an entire package division looking at the change in production, including but not limited to SPORH, for hundreds of drivers over every day for several weeks? Even when stops on a route go through the roof and the piece count does the same, typically SPORH does not usually make huge swings, in my experience. But neither my experience nor yours is relevant to this discussion.
For the sake of argument, let us say that a bricked out package car poorly loaded is a good and fair reason for a break down of 3 SPORH off demonstrated performance. Do you have any evidence that that happened to this driver, not just once, but over several days? You have not presented any.
All I said was that all else being equal, a drop of 3 SPORH over several days tends to point to a driver who is violating the contract by not giving a fair days work. I never said it was a certainty this was what happened. I am a fair minded member of management. So, if you have evidence that all was not equal over the several days that this drivers production went down so drastically, lets hear it. If the best you have is "sometimes playing hide and seek hurts production by 3 sporh" fine, all you have is possible, but rather implausible conjecture. In that case I agree that maybe, he was fired unfairly. You must admit however, that maybe he was not, at which juncture you should drop this attitude of it being a certainty that he was rail roaded and let down by the union and this whole thing is a wild injustice.
I will congratulate you on your victories over your management in your particular struggles, but remind you again, it has nothing to do with the case in question.