My experience is that whenever we issue a revised departure clearance ("after departure continue runway heading blahblahblah"), readback ends with "cleared for take-off", even though it was never mentioned - and that's from ATPLs, not PPLs. That's why we would always add at the beginning of such an instruction "hold position". You could argue it's superflous, the same way as ROCAS. But I don't think you will persuade majority of ATCOs.