The thing that erks me is pilots who report ready to Tower well before the holding point (in breach of the AIP). It takes others out of the loop, in particular when there are taxiways they have to cross. Saw a near miss when two 737s tried to taxi to Juliet one day as one reported too early to tower. I would have thought that this increases ATC workload if they have to communicate to aircraft that prematurely calls Tower. After ATC thoughts on this?