Your average airliner has flown thousands of flights and had tens of thousands of people eating peanuts on board. Each of them has probably dropped a few nuts which will have been ground into the furnishings. But these appear not to count. Also, the meals that were prepared using groundnut oil appear not to count. Nor do the carrot cakes containing nuts, smuggled on board by homicidal members of the public. Yet little Johnny will pop his clogs if I eat peanuts on the same flight? Now if that is a threat to that person's well being then they must not use public transport.
For the safety of the person suffering the allergy and my airline's bottom line, I am more than happy to deny them boarding. Not being medically qualified I am unable to state that anybody suffering any sort of chronic allergy will be safe on board my aircraft. Anyone could crush nut remanants and these would be dispersed rapidly by the aircraft's air conditioning system. Therefore, purely in the interest of the safety of sufferer I'd suggest their traveling needs will only be met by private transport.
PM