See it from the view of a local held wards:-
I’ll use the Heathrow area as an example:
Hayes & Harlington (held by none other than John McDonnel 15k majority for Labour)
Ealing & Southhall
Feltham & Heston
All Safe Labour Seats.
Brentford on the other hand along with Ealing central and Acton - are now both Labour Marginal with majorities of less than a 1000 in both cases.
Labour didn’t take many seats off the Tories in the election - but these two are right next door to each other…
The Tories took both Twickenham and Kingston seats off the Libdems just down the road to the southeast.
Now… There are not many ways you can alter the local boundaries so that the Tories can gain back - IF you decide to enlarge heathrow airport.
The Tories COULD be complacent, and alter the boundary so that the safe Tory seat of Uxbridge (BoJo’s!) might be re-drawn to throw some much-needed Tory voters into the Labour marginals nearby - at the expense of some of Uxbridge’s majority.
Boris is always going to be in favour of “no expansion in this entire area” - as is Mayor candidate Zac Goldsmith of course… They’re just protecting their own back yard.
Look how easily Cameron found an extra 10,000 Tory voters in Rochester and Strood - to unseat Mark Reckless - DESPITE him keeping pretty much the same number of votes for when he won for UKIP in the By-Election the previous autumn… Altering the boundaries allows “safe” voters (those whom you know in advance which way they’ll vote) so that the results of bordering wards can be manipulated.
If Cameron could magic up an extra 10,000 votes for Skelly Tollhurts which represented his “throwing the kitchen sink at it to kick Reckless’ arse out of westminster” - then imagine what he could do at the NEXT election - by altering the boundaries around Heathrow airport to easily take back both Labour marginals in the area - and weaken the Shadow Chancellor into the bargain as well!
This assumes of course the Libdems don’t make a significant recovery in time for 2020 - but how could they? They are heading for extinction now… It took DECADES to get the Libdem vote up as high as it was - only for it to be dashed asunder, Cameron also palming off blame for “government dithering” over the Somerset Levels issue - upon Cleggy & Co.
That’s politics folks - It’s far easier to stab around with the knife when you’re in office - rather than out of it.
Compare that to Corbyn who’s been an MP for yonks - and only has a reputation for futile deeds, and not actually getting anything done whatsoever - His party or the opposite…
Corbyn might have more parliamentary experience than Cameron (as did Milliband) - but let’s face it - Cameron ■■■■■■ all over the pair of them, and is likely to keep doing so. He knows damned well what Blair tried out experimentally - and got away with - and he’ll make use of those observations to achieve the same type of goals for his own ends…