Two points:
Via Aylesbury? I think the BBC» have got it wrong. They probably mean a separate route from Aylesbury to Milton, and Oxford to Bedford.
And why only 100 mph? The section east of Bicester is pretty straight, and has no points for stations until Bletchley! 125 mph please!
I should think the people of Winslow, population getting on for 10,000, would quite like the trains to stop at their town along the way... also a couple of other stations are proposed between here and Bletchley where more housing is slated to go in as Milton Keynes grows. The proposed East-West service mix includes stoppers and semi-fasts to cater for the various markets.
MK▸ -Aylesbury, via Claydon junction, is an aspiration of the East-West consortium.
100mph is fine for this sort of route, with relatively frequent stops and Chiltern's trains are unlikely to make that many calls at Islip anyway, Water Eaton Parkway (aka Kidlington) being a far juicer prospect, by saving people the struggle through the city to Oxford station.
Electrification won't be happening at the initial stage, but if
GWML▸ and
MML» wires get the go-ahead, followed by
XC▸ , then Oxford-Bletchley-Bedford would be an obviously useful bit of infill, allowing freight diversions in particular when regular routes are blocked/under maintenance.
Class 168s, like other Turbostars, are already cleared for 100mph.