This thread made me think of the discussion and drive for East west Rail - eg not specifically about stopping Intercity trains at St Albans - but how far out do you need to go before you pass the frustration point where it is irritating to travel in the wrong direction into London, but insufficiently far to stop intercity trains without slowing long distance travellers unnecessarily.
It would seem ideal, going forward, for there to be a decently speedy route linking the main lines, and ideally the Great Eastern and great western too, with those being part of regular stopping patterns so that people from WCML stations could travel reasonably to northern ECML stations where the journey planner would currently route them via London. Agreeing a point for that route to cross the MML and stopping a reasonable number of trains there, would seem a very sensible idea - in the same way as Orbirail, or east west rail, or whatever we want to call it - should really exist on a number of levels and a number of crossing points, for example Luton To Stevenage, a short 14 mile hop just shy of half an hour by road, the rail journey takes 2 and a half times as long (even the bus is a little quicker), and involves a cross platform change at St Pancras - 33 miles away. These are not insignificant settlements, and London is far from the only destination.