All boils down to the fact if you ask (say) 10 controllers a question, you'll get 20 different answers.
Landing at Heathrow in a Brymon Herald (yes it was many years ago) we could hear a Trident catching us up. He reported OM well before we touched down and we had delayed landing clearance due to the 'Link' helicopter crossing ahead. The controller (possibly talkdownman?) kept telling the Trident 'continue' and just as we started to exit the runway the Trident said 'I'm on the deck' to which the controller replied 'cleared to land'!!