But under FPTP the opposition votes would be spread, Lab/Lib in England, SNP/Lib in Scotland, and Plaid/Lab in Wales so whilst they might collectively garner a majority of the votes, unless the Brexit bunch significantly split the Tory vote, ( without taking too many from Labour ), the Tories could still end up as the biggest party at Westminster. An electoral pact between the opposition parties, however, might change things in their collective favour.