I was taught that it is not good flying practise to hold the nosewheel off, for a number of reasons:
1. Boeing teach that as soon as the main gear is down the nose gear should be positively 'flown on' to the runway, i.e. a Small check forward to achieve a gentle contact. The benefits of aerodynamic breaking are, they say, far outweighed by the benefits of the increased drag from the nose-wheels and the reverse thrust vector is more effective the more horizontal it is as it is directly opposing forward speed and not at an angle.
2. Less chance of a tail strike by putting the nose down immediately after the main gear, particularly if you get caught by even a small gust and you only have minimal elevator control.
3. Unless the final touch down of the nose wheel is very carefully controlled then holding it off can cause it to eventually thump/drop down when elevator control is lost. Continual 'thumping' not good for the engineering! By putting it down when elevator control is still very effective a gentle contact can be achieved.
The above are offered as discussion points as I know there are a variety of theories out there!
