Because it was done on an 'as needed' basis, the distinction I would make is that these shutdowns (IIRC) were to deal with acute issues. A more regularized sche

Because it was done on an 'as needed' basis, the distinction I would make is that these shutdowns (IIRC) were to deal with acute issues. A more regularized schedule, where shutdowns are part of normal operation and are documented well in advance might lead to a situation where problems (like those on the L) are less frequent to begin with.