Alternate History Impact of two stage (like French) voing system on UK in 1983?

[Buba]

In 1983 in the UK the vote split c. 42,5-27,5-25,5% between Con, Lab and Dem-Lib.
FPTP produced the following split of seats:

397

209

23

I am too lazy - and not THAT curious - as to go constutuency by constituency to see what could the use of the two stage system as used by France today* produced.
Could 2nd stage alliances between Tory and Lib-Dem - Tory voters tactically voting Dem-Lib instead of going fishing - killed Labour, i.e. reversed their seats?

Maybe has been asked before, maybe even by me - sclerosis galopans for teh win!

* winner must have 50% or better of votes in 1st round, or there is a play off between best finishers (usualy two, but a complicated by-rule occasionaly produces threeway contests in 2nd round).

 

[49ersfootball]

In 1983 in the UK the vote split c. 42,5-27,5-25,5% between Con, Lab and Dem-Lib.
FPTP produced the following split of seats:

397

209

23

I am too lazy - and not THAT curious - as to go constutuency by constituency to see what could the use of the two stage system as used by France today* produced.
Could 2nd stage alliances between Tory and Lib-Dem - Tory voters tactically voting Dem-Lib instead of going fishing - killed Labour, i.e. reversed their seats?

Maybe has been asked before, maybe even by me - sclerosis galopans for teh win!

* winner must have 50% or better of votes in 1st round, or there is a play off between best finishers (usualy two, but a complicated by-rule occasionaly produces threeway contests in 2nd round).

Following this discussion thread very closely with lots of intriguing interest!