Well I'm sorry to read about your bad experience. I'm in T5 Connections at least once a week, sometimes 2 or 3 times a week, and I deliberately aim for 60 to 90 minute connections, on the basis that I wasn't put on this planet to spend time in an enormous warehouse, no matter how well appointed. So far this year I've not missed one connection, including some that end up being 45 minutes due to delays. Last year I missed a few, but I didn't spend that long being rebooked. Heathrow's workload does vary enormously, if flying mid week during the middle of the day, or Saturdays, T5 can look quite empty.