> I'm 100% against new tracks being laid or any more capital expenditures...the current system needs better maintenance, first.
Maintenance of the current system requires capital expenditures. It becomes expensive to run old trains on old signaling systems, which is why both are being upgraded for the Red and Orange lines. It's expensive to be poor, and watching the MBTA operate try to operate is a heart-wrenching example of this. The downtown transfer stations are expensive failure points in part because they're handling the demand of Red <> Blue commuters who don't have a direct transfer at Charles/MGH because that would be "capital expenditures". It costs the MBTA more than $100 million in operational overhead yearly because the northern and southern halves of the commuter rail don't connect. [1]
> Here's one solution: create a new express lane on existing highways by removing a lane or repurposing the existing HOV lane. Make this new lane have a 80mph speed limit. Only allow buses. There you go.
The problem of urban transit is very rarely just how to move people quickly between stations — it's about how to insert them efficiently within walking distance of their destination. Previous generations were kind enough to leave us with a commuter rail system that is remarkably good at doing that across many towns in the region, and the solution — run more and better trains — is blindingly simple.
> but once you consider the commuter rail is already underutilized it's hard to imagine
The commuter rail carries 42% of passengers bound for Boston at rush hour so "underutilized" is a relative term. [2] The infrastructure (trainsets and railyards) makes it hard to run more efficiently at off-peak hours, which is again an operational cost that can be offset over time with capital expenditure.
[1] https://static1.squarespace.com/static/561e6ed5e4b039248a6a9... (table EX-3 on page EX-10)
[2] http://amateurplanner.blogspot.com/2017/03/how-many-people-u...