All of a sudden and seemingly with neither warning nor much explanation, the MTR Corporation has decided to prohibit passengers from taking large musical instruments such as cellos and guzheng (a popular traditional Chinese stringed instrument) onto trains.

Musicians conducted (or is orchestrated?) a protest in Tai Wai Station.

But, went the response, rules are rules, and cellos violate the maximum total dimensions of 170 cm. The MTR has been getting a lot of flak for allowing the trains to be used as commercial transportation by parallel traders: Photos of washing machines, mattresses and trolleys piled high with cartons have shown up on social media and elsewhere. So it would appear that once the MTR decided to crack down, some in the organization felt it had to do so without fear or favor.

Fair enough ... Well, not really. Actually it is a silly policy, as the resulting outcry makes evident. There are not very many people traveling on the MTR with cellos: I can't quite recall ever having seen one. This can't, except for some need to standardize the rules, be a big problem. And therefore, not least because it is proving a major public relations headache for the MTR (even Singapore has weighed in), it seems reasonable to assume that it will soon be resolved on its own without the assistance of op-ed writers.

But the question does present a potential teachable moment about accommodating outliers in a crowded city.

This problem underlying the regulation is surely not, as some commentary has had it, fundamentally one of "space" in the carriages, for if it were, backpacks and very large passengers would present similar issues. And if space were the issue, then one solution sometimes mooted - charging an extra ticket for the instrument - would solve nothing: If the argument is that a cello denies a human being space on the train, charging extra may generate more income for the MTR but still leaves the excluded passenger on the platform.

But space is almost certainly not the issue: The problem with larger, bulky luggage is that it is not very maneuverable, can bump into people and can cause congestion in the carriage and upon entering and exiting. The more crowded the carriage and platform, the worse this problem is.

Nevertheless, musicians and music students need, in most cases, to take their instruments with them from home to class or to their orchestra; musicians without their instruments almost cease to be musicians. Pole vaulters, by contrast, do not usually practice at home - they can leave their tools of trade at the office.

Whether or not Hong Kong should want more people to take up a musical instrument (it probably should), there is no reason to discourage them unduly. And all things being equal, one would want the choice of instrument to be as independent as possible from extraneous considerations such as transportation - orchestras need more than just piccolo players.

Restricting travel to off-peak hours only works if musicians never have to travel at peak hours; one suspects that musicians are, in this matter, not much different than anyone else.

Musicians, in other words, are people just like the less-talented rest of us. The purpose of public transport is to transport the public, and it is not really a musician's fault that the vocation comes with an instrument.

Musical instruments might therefore be considered similar to wheelchairs and guide dogs, which are exempted from other applicable regulations which otherwise prohibit Segways and pets. Perhaps not all instruments of course - one might draw a line at, say, pianos, kettle drums and pipe organs.

If musical instruments are given an exemption, then these exemptions can come with conditions. One might be required to register the instrument, perhaps gratis or perhaps for some nominal annual fee; a label or pass would remove the necessity for train staff to make ad hoc decisions. Such exempted items might be restricted to the first or last carriage, where there is usually less congestion. And, finally, such items could be subject to spot inspections (to ensure that the label hasn't been re-applied to a refrigerator or that the double bass case isn't in fact filled with tins of baby formula).

There just aren't that many cellists or guzheng players in Hong Kong. Nor is the number likely to grow if they receive this accommodation, for classical music is not a high-growth industry.

And there you go. A straightforward solution to a not very large problem which in turn provides a paradigm for looking at other requests for accommodation on public transport or elsewhere. The questions are simple. How big is the group requesting accommodation? Will accommodation tend to increase it? Do the activities of the group in question have a social benefit? Can the group or accommodation be tightly defined so it is clear which situations the special treatment applies to?

MTR trains may travel without conductors, but there is no great need to exclude musicians as well.

(HK Edition 10/26/2015 page10)