That tunnel thing is one of those that comes up with regularity every few years, in the same way as the 'skyway' thing (although the latter more frequently). As others have said, it is entirely impractical and can safely be ignored.
@Oliver Schick started
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That tunnel thing is one of those that comes up with regularity every few years, in the same way as the 'skyway' thing (although the latter more frequently). As others have said, it is entirely impractical and can safely be ignored.