Most of the rarest twentieth century US stamps are either coils or coil waste (“coil waste” are stamps that were prepared to be issued as coils, but later additional perforations were officially put on the stamps, and they were issued as regular postage stamps). Coils present an unusual problem for collectors in that they are so hard to authenticate. It is easy for a forger or stamp alterer to cut the perforations off the edges of a regular stamp to produce a rare coil or add perforations to an imperforate stamp. This is why valuable US flat press coils (those with Scott numbers before #448) should only be bought with expertization certificates. This warning is given in the Scott catalog, and it is good advice.
But coils have really complicated US collecting and not only because there are so many fakes made from perforating imperf stamps and cutting the perfs off of perforated ones. Coils have complicated US stamp collecting because they have created a US collecting paradigm that is quite at variance with the way stamps are collected in the rest of the world and one that doesn’t make much sense. Collectors of European stamps, which are collected by the German Michel catalog or the French Yvert catalog (and the Scott listings for such countries as Germany and France are largely derived from these catalogs) are largely face different catalog listings. Where there is a variety, such as a shade, perforation or paper, the variety is listed an “a” number of the major listing. Thus the albums have spaces for only the major stamps, and it is only specialists that delve into the intricacies of scarce perforations and coils. This makes collecting these countries much easier and makes forgeries of minor varieties much less common as there is far less demand for the variety than if it was a major number, and the collectors of such varieties are far more knowledgeable than general collectors and are less apt to be fooled by fakes (and thus fakers are less apt to make them).
But what we have in US philately in thirty or so major Scott number listings for the early twentieth century that every US album has spaces for and that every collector needs. And all of these rare coils have ten times as many fakes as every genuine one. Collectors are often defrauded or fooled into believing they either own or have inherited great rarities that are in fact worthless. The reason this silliness was tolerated was that the early dealer network that controlled the Scott catalog also controlled the supply of genuine coils that they bought out as they were issued from the postal service. These stamps, in reality minor varieties of more common fully perforated stamps, were elevated to full number Scott catalog status (thus insuring all US collectors needed them) because there was money to be made. The situation should have been corrected seventy-five or a hundred years ago. But what we have now is a system that lists varieties as major numbers, creates incentive for fraud, and makes it so that very few US collectors can ever complete their twentieth century US collections.
So do you think there will be change and Scott will come to have more rational listings? I think you could bet your house that it won’t happen. In philately, as in much of life, no matter how dumb or irrational something is, the longer it has been in existence, the harder it is to change. The rationale “that’s the way we’ve always done it” routinely defeats the soundest reasoning. In this we can take solace that our hobby is little different than most things in the world.