Which 'reg' states "1000' AGL unless Landing,Taking Off, or due stress of weather..."? As far as I recall, not having the ANO to hand, Rule 5(1)(e) states only that an aircraft shall not be flown within 500' of any person, vessel, vehicle or structure unless taking off or landing in accordance with normal aviation practice. There is no indication of what is considered to be 'normal aviation practice' nor a minimum height for commencing a noise abatement procedure after take off or even a minimum height for commencing the first turn after take-off. I can think of a number of (mainly GA) airfield which have noise abatement procedures commencing below 500' agl.
Whether such a procedure is sensible is a matter of personal opinion and depends upon that, seemingly now unfashionable, idea called Airmanship. In this case the procedure is not publicised in the AIP, you (the pilot-in-command) consider it to be dangerous - don't comply with it. After all, your responsibility for the safety of your aircraft and all it's occupants can override the provisions of the AIP and the ANO in certain circumstances. You may, of course, have to justify that in court if the CAA disagree with your assessment of the danger.