AFAIK it's normally one person per tag. Remember that these scumbags are
generally young / unemployed / unemployable so can dedicate their whole
day
to this ...

You seem to know too much about this matter :-)
More should be done to stop this (see: "Ways to Reduce Vandalism" Thread)
such as Live CCTV monitoring with communication between CCTV operators and
station staff, drivers and police officers.
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To reply direct, Remove NOSPAM and Replace with 21fun
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