That's still something that wouldn't be that difficult to change in the future. Probably easier to fund once the initial system is operational and the case for the extra expenditure is clearly demonstrable.
Having it connect into Caltrain is probably something that is nice to have anyway (like if there's maintenance required in the hypothetical tunnel or whatever kind of direct bypass, so you can still run services on the slower route) so it's not a waste to have both.
Having it connect into Caltrain is probably something that is nice to have anyway (like if there's maintenance required in the hypothetical tunnel or whatever kind of direct bypass, so you can still run services on the slower route) so it's not a waste to have both.