The number of times that I’ve gone on to the online shop and seen planes described as the above are countless. It is perhaps sellers that have limited knowledge of hand tools shooting in the dark, hoping that the mere mention of the 3 great makers names will increase the price they receive.
The truth is that each of these makers had a slightly different take on the infill plane, subtle differences that can be noticed after nearly 20 years of collecting. A veteran collector can spot a quality plane at 20 paces across a busy room. The most common misdescribed plane is one with a Mathieson blade. The only thing that is known for sure is that it has a Mathieson blade.
Does all this really matter, to the user no, each plane will be judged on its individual qualities? To a collector yes, it’s about the name, I personally have a couple of Mathieson planes probably made by Spiers, no marking on the lever caps but faintly marked Mathieson on the front bun(Not an uncommon practice for these plane makers to do work for each other.) Would I get top price for these 2 planes, probably not even though they are both in fine condition?