General Election June 2017

So, with a working 'Government' majority of 2, Ken Clarke is suddenly in a position to cause no end of trouble ...

Not really. The majority isn't the number of MPs over 326, it's the difference between the Government MPs and the opposition MPs with a few other bits to take into consideration (the numbers change each year due to Sinn Fein):-

650 (seats) - 1 (Speaker) and 7 (Sinn Fein who don't sit in parliament ever) = 642

642 - 318 (Tories) - 10 (DUP) = 314 possible opposition

So the effective majority is 328 - 314 = 14

So they could survive 6 MPs voting against the party (making it 322 to 320). A 7th would tie it 321 to 321 in which case the Speaker would generally vote for the status quo (https://en.wikipedia.org/wiki/Speaker_Denison%27s_rule) so this needs to be avoided.

Labour's 1997 landslide of 418 MPs (out of 659) was (strict) majority of 179 (including the speaker).

659 - 2 (Sinn Fein) = 657

657 - 418 = 239 opposition

418 - 239 = 179 majority