That must have been me, I'll take the complement here, thanks!


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I suppose you are right, even though a more appropriate reply (in the scenario I mentioned) might be
"As you were informed at the time by the member of staff and your letter has confirmed to us, you were in breach of the NRCoC and railway bylaws (insert as appropriate), and not only was your behaviour causing a disturbance to passengers, your threats to staff were unacceptable. We will not proceed to prosecution on this occasion, but as your details are now on our file, if you are detected in any further breach, prosecution is likely to follow".
Although this would be in line with TOC's much-touted zero tolerance and 100% support of their staff when confronted by anti-social behaviour, I can't see it happening anytime soon.