BART and MUNI have fundamentally different orientations, despite overlapping service along the Market Street subway.
BART's service is long-train (up to 10 cars) through service on fully dedicated trackways following a single through route within San Francisco. If you happen to be transiting any points between Colma and Embarcadero strickly along that route, BART is your best bet.
MUNI Metro serves multiple endpoints throughout San Francisco, several lines of which transit the upper level of the Market Street subway. Outside that route, the metro shares rights of way with street traffic, resulting in drastically less predictable schedules. The requirement to manage tight-radius curves and street traffic also limits the length of metro trainsets to a maximum of two coupled trolleys.
The results aren't pretty, for MUNI. But that's all but a given under the environment they're operating in.
>The results aren't pretty, for MUNI. But that's all but a given under the environment they're operating in.
Not necessarily. They could exclusively run fast 4 car trains along the length of the subway, with transfers to street lines. That would prevent a single street-level train from backing up the whole system. http://newmunimetro.com/m-market/
That's a possibility, though there's a long history of transit users prefering through routes rather than transfers. If Muni could maintain 4 minute headways (or shorter), consistently, in the subway, that might be an option. It would reduce the wait times inbound on the subway to an average of 2 minutes, which is tolerable.
You still end up with the service irregularities on the surface sections, unless those rights of way are dedicated. Something which really should have happened long ago on Geary and Irving/Judah, 3rd St., etc. Maybe with the dedicated transit route on Market the idea will spread.
Extending the subway further out is another option, though expensive and fairly unlikely.
BART's service is long-train (up to 10 cars) through service on fully dedicated trackways following a single through route within San Francisco. If you happen to be transiting any points between Colma and Embarcadero strickly along that route, BART is your best bet.
MUNI Metro serves multiple endpoints throughout San Francisco, several lines of which transit the upper level of the Market Street subway. Outside that route, the metro shares rights of way with street traffic, resulting in drastically less predictable schedules. The requirement to manage tight-radius curves and street traffic also limits the length of metro trainsets to a maximum of two coupled trolleys.
The results aren't pretty, for MUNI. But that's all but a given under the environment they're operating in.