The 172s that you're waiting for are in an exactly analogous situation to the 153s in question - they've all now been withdrawn from the (heavily overcrowded) Gospel Oak - Barking line so that they can be modified to West Midland Trains' specification. The GOBLIN timetable has been reduced from quarter hourly to half hourly as a result.
It's inconsistent to object to the 153s being withdrawn for conversion to alleviate West Highland overcrowding, while expecting the 172s to be withdrawn from their previous home to benefit West Midlands services.
[edited to remove confusing abbreviations]
I haven't said a word on this thread that could imply I 'expected' the 172's to be withdrawn. The goblin passengers have been treated poorly, although thankfully at least they still have a service and the same capacity per hour. Hats of to TFL for arranging the short term fix.
However the 172's have been withdrawn for use up here, and crew training is now well underway.
What I am annoyed at is that off lease rolling stock has been sent for conversion to carry bikes, when passengers are being left behind on routes where these units could have made an impact at least in the short term.
I don't doubt that the WHL needs these dogboxes to ease overcrowding in the summer, but space for passengers should always take priority over bikes.