"This is correct once you've flown the first leg. It is a silly policy IMHO, but what they're telling you is correct. Also, it hasn't really cost you 25K - it's 12,500 as you presumably did benefit from the MFU'd first leg."

Sorry but I know it is the rules, I'm trying to find out what kind of mean spirited mentality in an organisation trying to encourage business travellers would come up with a set of rule like this.

I'm 1k with United too and the difference with BAs grudging appraoch couldn't be greater.

PS - Yes sorry, I do know it is 12,500 thanks for the correction...