I feel like we are going round in circles a bit here. But the point would be that the 'core' vote has changed a lot over time, and will change again depending on decisions the party take. The 'core' and 'swing' groups aren't fixed.The game is to do enough to keep your cove vote happy while appealing to swing voter in the process. The modern labour party does not win elections by only appealing to its core vote. Did the party not learn fuck all from the wilderness years?
none of the last two elections were lost because the party wasn't left wing enough