Lots and lots of agreement here, and all excellent points.
Interesting analysis. The problem I have with SCR is that it gives a big whiff of either being designed to fail, or at least designed with a near-total indifference to whether or not it fails.
Yes, I agree with this. I think it's worth examining our definition of "failure" though, and I'll come back to that below.
The problem is that the single-track Old Colony main (which the state resolutely refuses to do...anything...about) can only handle so many trains. FR/NB are never going to get the kind of robust schedules that make transit/rail really useful, and sparse schedules are even more of a problem when the travel times are as long as those routes are going to be. So while it's being done, and being done by the cheaper, faster, and easier route, that choice means a trade-off in terms of usability.
I think that's a problem for two reasons beyond the fact that it's poor service for FR/NB. The first reason is that it comes at the expense of headaches for efforts to bring the CR to Buzzards Bay because it eats up so much of the Old Colony's remaining capacity. FR/NB could be served by an alternate routing that doesn't touch the OC, Buzzards can't be, and I don't like that they (and potential Cape service) get screwed by this when it didn't have to happen.
I agree 100% -- the routing via Middleboro is disastrous for both of these reasons.
The other reason, and the big one why I can't really agree with your thesis in its entirety, is that by building it on the cheap the way they are, and particularly because of the poor schedules that will inevitably result because of the main line's capacity crunch, they're at the very least running a huge risk of artificially suppressing ridership. Globe articles about underwhelming ridership might not undo infrastructure improvements, but they sure as heck give Baker & Company all the cover they need to never touch the idea again, leaving it permanently broken (and potentially taking Buzzards/Cape with it), or even killing it off next time there's a budget crunch and it needs to be "temporarily suspended" only to never restore it because we tried it and know that the ridership isn't there, even if that's only because it was done wrong.
So I don't actually disagree with you here. I think what you describe is entirely possible, and even to some extent likely.
However, Baker won't be king forever. And even the current "Massachusetts Republican Governor" vogue won't last forever. On a hundred-year timescale, eventually
someone will come along and be willing to "unbreak" this mess -- particularly since advocates will have had plenty of time to narrow their focus to something like "Double track the Old Colony Main" or "Build the Taunton Rail Connector" or "Build the new Mansfield Junction".
Now, I do worry about service suspension and then a lack of maintenance. That is a gamble here, I agree. If the stations or rails are left to deteriorate completely, then we're back to square one. (Although can you imagine the optics?)
But, to my knowledge, no commuter rail service in the US or Canada has been indefinitely suspended in the last... 20 years? The most recent one I can think of is the Lower Boonton Line on New Jersey Transit, but that was replaced by a service just a mile or two away and so doesn't really count. Shore Line East, Wickford Junction, Greenbush... once (mainline) trains start running somewhere, it seems extremely rare that they get eliminated outright.
(I will grant that there have been one-off suspensions: Gardner, Plymouth, Foxboro. But I think that's different than shutting down an entire subnetwork. I may be splitting hairs here, but I'll stand by it.)
(And I could be wrong about the lack of large suspensions -- my knowledge is not exhaustive. That being said, I
think I'm pretty familiar with systems on the scale of South Coast Rail, so I feel modestly confident.)
So Baker or his successors just shutting down the service due to low ridership seems unlikely to me. Yes, there will be artificially depressed ridership for certain, and it will be up to advocates to continue holding the state's feet to the fire.
I am entirely in agreement that it's usually a good idea to build even if the project is less than ideal. I'm not convinced that that's true in this case, between the trade-offs and the elevated risk that getting it wrong dooms the entire prospect of ever doing it right.
And I'll say that I am very sympathetic to this view, as it's the same way I had felt for a number of years. I could very well be wrong -- 20 years from now, I might look back and shake my head at my naïveté. But I think it goes back to the question -- what do we mean by failure? And the more I think about the long view, the more I feel that the short-term negatives are outweighed by the long-term positives -- and certainly outweigh the do-nothing alternative, which I truly believe is the only other option at this point. If we have to wait til the Stoughton alignment is squared away before doing the Southern Triangle, I firmly believe this will never get built.