One design element, I think is present, is the large trench under the grating below the cars.
I'm wondering if the point to the trench design is to allow the air to flow under the car to lessen air resistance.
From a first order analysis of aerodynamics, a trench doesn't really matter. What matters is the cross section ratio between the train/pod/carriage and the bore--a trench would simply be the result of trying to maximize that ratio in a configuration that uses wide rails. If the Boring solution ends up with something similar to legacy rails, there will be no trench and the aerodynamic solution of the carriages will look something like what we currently see with high speed rail. Of course, there's a lot of value in tying rails on solid ground (like legacy rails) over mounting them spread far apart and on either side of a trench, but certainly if anyone can make wide rails work its Boring. But...it won't be cheap or easy--wide rails would be a sub-optimized element of a bigger picture optimization.
WRT seating/standing: I don't think they'd want different configurations because it would be much more convenient to have the same car switch between local (<2 km) and long distance (<20 km) journeys without reconfiguration.
Boring absolutely wants different seating configurations--they absolutely want units optimized to do this or that, and they absolutely want the ability to reconfigure them based on actual usage. Its very similar to the aircraft model--you can buy a 737 airframe and turn it into a two class pax, a one class pax (economy or business), a split pax/freighter, a BBJ, a C-40, etc...then when someone buys your 737 they can reconfigure. The good thing about Boring is that there will be another layer of configuration similar to the auto industry (including the S/X skateboard) where a commonized base vehicle can be permanently fitted to serve all manner of transportation needs (its also kind of like the aircraft industry where you can get a long haul or a short haul model on similar airframes).
If you're talking daily reconfigurable, then I'd agree its unlikely they want to do that, but again if anyone can make it work its Boring.
One issue with standing is that it seriously limits accelerations, which in turn requires longer on/off ramps and turn radii.
Of course. However, as previously noted, mandatory seating demands an aircraft-like passenger safety experience (and specifically the time component), which is a total non-starter for intra-city travel. Its also hard to imagine mandatory seating enabling a big enough time delta for longer trips either. Faster accel/decel saves seconds. Slower aircraft-like boarding and de-boarding wastes minutes.
Also as previously noted, there's an opportunity for Boring to design roll and potentially even pitch control of passenger pods to reduce unpleasant g-loads on passengers.
I'm not sure the 737 analogy is relevant since they plane uses the bottom of the cylinder for cargo which wouldn't be the case with the Loop cars. For the Loop, the "aisle" will be much lower, therefore narrower.
Its important to maintain context in multi-faceted discussions--in this case context is specifically the suggestion that Boring pods should have tube-like overhung walls/ceilings. I think we can all agree that the only real reason to have such a feature is if you're trying to maximize the width of a bore. As such, the 737 mental exercise is very relevant in context because it fairly accurately represents such width optimization exercise. And that exercise clearly illustrates there's no need for the overhung tube-like walls/ceilings. Its also very relevant because [again] regardless if your pax are sitting or standing, the pax deck height in a 737 is pretty well optimized for maximizing width within that cross section. In other words, if Boring was trying to maximize bore width, the cross section of the whole thing would look quite similar to a 737.
Personally I don't think maximizing bore width is the ideal way to maximize the system efficiency (I think longer trains that minimize aerodynamic cross section is a better overall solution), and I think we can all agree that if you
aren't trying to maximize bore width, you just make your carriage walls vertical-ish, similar to the sub-surface Tube carriages. Of course they'l have
some profile that's aerodynamically efficient, but nothing like what we see on a small Tube carriage.
Overall, I'm surprised they went with 14' tunnels. Smaller tunnels are cheaper and faster to dig as well as being stronger.
Interesting perspective. IMHO, 14' seems like an obvious
lower bounding condition. 12', for instance, puts the aircraft analogy somewhere closer to the cabin of an MD-80/717, and anyone who's been on the small Tube lines knows how cramped they can get. 12' all but eliminates the possibility of using the system to transport ISO containers (which are 8' wide and 8.5' tall). Smaller being stronger is a bit of a straw man--there's plenty of lager tunnels in the world. Cheaper/faster is a bit too narrow--optimizing the system is more important than optimizing a single element, like construction.
