I thought weather interline reroutes were SOP. They seem to be for me anyway!
Stupid Florida summer weather.
That said, thanks for the tip about asking the AAgent to note "Original Routing Credit" in my PNR. I'll keep that in mind next time.
It was quite fortuitous that they did interlin eme that night. After sitting at TPA for ~6 hours we arrived in LAs abotu 20 minutes after the original scheduled time. I absolutely HAD to be there, too. Overall I was happy with AA's handling of the situation.