woofe..i know exactly what you are saying, spent 3 years in the desert...but never the less, in the middle of summer one could encouter icing in the north, algiers or constantine.
if what you are saying was the case, why did beechcraft not say in their mel, not applicable if in temperatures exceedind 45 degrees?
you know, we accept the manufacturer to know more than ourselves when it comes to limitations, checklists, normal, abnormal, and emergency, we accpet their mass and balance, and yet you still claim to know better than their people who wrote the mel/mmel?
i just dont understand the logic?
the whole point is, if you cannot afford to run the operation legally then you should not do it.
your example is fine, it is middle of summer and prop blade de-icing is u/s, you agree to accept the plane as is and it is not written in the flight folio, that is all well and good, but unfortunately, the sa operators then see you do this and it is not chased up or conisdered important enough to put on a priority, instead the snag is just left to be forgotten and next thing you know, the seasons have changed and it is autumn and winter and still not fixed and i am due to fly the plane and i read back in the highly illegal unofficial snag book and see this snagged and not written up as fixed...so i say, no, i am not flying this because we might encounter icing conditions....to which the reply is...but everyone else was flying it before, who are you to now say you wont fly it?
why not just implement a better maintenance set up, an effecient method of ordering and tracking spares, and engineers capable of being able to do the necessary in field maintenance, then everything is correct, proper and legal.
but that would be doing it properly and therefore not in the business plan of an sa operator!