Looking at Mauritius prices, this looks tempting, however I can't get my chosen itin to validate (must be getting rusty on the rules).

Thinking of something along the lines of:

MRU-LHR-THR-LHR-IST-LHR-GRU-SCL-IPC-xSCL-EZE-xLHR-CPT-xLHR-MRU.

As far as I can work out, I come unstuck on passing through LON too many times - even though there's no way to get back to Africa from South America without first passing through London.

Any suggestions for how to fine tune this?