I was on a routing of DEL-FRA (LH) - LRH (LH) - IAD (UA). LH complained about me exceeding the weight limit on my bags. I mentioned the final UA connection (that was 2 days later and hence I was not getting a BP). The agent checked with his supe who verified that all legs were on the same tix. He said that made my weight allowance based on UA policy and hence ok. I was surprised as the tix was LH issued with only one final leg being UA. Anyways, it worked out fine for me.