[You must be registered and logged in to see this link.]Bob_C in the comments section on the link said it better than i ever could. In case it goes missing and probably will here is what he said.
"Bob_C | January 02 2015, 9:23AM
He was an eccentric and probably the most disastrous leader the Labour Party ever had. By all means have a memorial to this son of Plymouth but don't make him out to be something he wasn't"
The slab looks like an eyeshore to me.