Decimate

Apparently 'literally' now means the way it is frequently used.

You're quite right, Greatnan. That is one which I find annoying too. I take your point, janeainsworth, but I must be too set in my ways as I don't care if it's a modern usage [grumpy old woman emoticon]!

Jen

They'd have to lose ten seats in order to kill off one of the ten to be properly decimated. Who would get to choose? Nick can never make his mind up. Neither can Vince.

Ah yes Greatnan, but (one of) the modern meanings of 'decimate', according to the Oxford dictionary, is to 'drastically reduce the strength or effectiveness of (something)':
e.g., public transport has been decimated
To cut by one-tenth is a historical use.
oxforddictionaries.com/definition/english/decimate
So the commentator was not wrong,if you accept that losing 5 or 6 seats woulkdn't drastically reduce the Lib Dems' strength.
But you were right too (in a sense).