still don't get it, sorry, oh now I do...
so based on population then, wouldn't pr fix that?
PR would mitigate the impact quite a bit, although exactly how much depends on the system and constituency layout used.
would all the people that moved be tory supporters?
If so wouldn't the place they moved to be more likely to be tory?
Not necessarily, but on a broad look, inner cities are far more likely to be Labour than other areas, and suburbs and rural areas are far more likely to be conservative or lib dem.
The reason the constituncy results don't match the popular vote is due to unequal sizes, for example:
hypothetical Safe Labour seat
Population: 40,000
Labour vote: 20,000 (50%)
Tory vote: 10,000 (25%)
LD vote: 10,000 (25%)
Returns Labour MP.
Hypothetical rural seat.
Population: 80,000
Tory vote: 40,000 (50%)
Labour vote: 20,000 (25%)
LD vote: 20,000 (25%)
Returns Conservative MP
Vote totals
Population: 120,000
Labour vote: 40,000 (33%)
Tory vote: 50,000 (42%)
LD vote: 30,000 (25%)
MPs
1 Labour
1 Conservative
0 LD.
Now multiply that across multiple constituencies.
This is what is happening and why the Tories need such a massive swing to get power, and Labour do not. (It's not a new problem, the same thing has been happening for a long time, Labour did worse this year than the tories did in 1997, but reverse the results from the election and the same thing happens), and also partly why the lib dems get shafted.
sounds a crap theory to me.
Except the results clearly show it isn't.