Indeed, and for what it's worth, my personal view is essentially that all that matters about a connector block is that it is big enough to accommodate the conductors concerned. I would nearly always do as you describe, but even if conductors are only put into one side, not extending to the other, the metal of the connector will virtually (quite probably literally) always have a greater CSA than the conductors - so I can't really get excited about the 'current rating' of the connector.
However, as you says, views about this can (and do!) vary!
Kind Regards, John