The late Sheldon Brown will surely be remembered as the first patron saint of internet cycling lore and has been for me personally an inspiration for technical writing. But none of that mitigates the fact that spelling derailleur as “derailer” is just stupid. The earliest derailleur was created by a Frenchman, the first widely available designs were French, the first commercially successful British products were from a company established through a French partnership, and everyone already spells it “derailleur”.
Sheldon Brown argued that there is a precedent in the English for a railroad mechanism called a “derailer”, but the supposition is that locomotives are more relevant to bicycles than a French invention to move a chain across a cogset.
There is L’Academie francaise (the French Academy), an institution in France, that among other things protects the Frenchness of the language from contaminants like the phrase “quarter pounder with cheese”. A few years ago, the French Academy decreed that the word “email” was un-French and mandated that France would use the word “courriel”. This is short for courrier electronique, the direct transliteration of “electronic mail”. Ever since then, all the French now have a cafe and a croissant in the morning before reading their personal “courriel”.
WAIT! No, they don’t! …because that’s STUPID and everyone knows it to be so. In a gratifying vote for pragmatism, the average Frenchman recognizes the primacy of the Anglo-American word “email” and choses both the status quo and universal clarity.
So remember, kids: D-E-R-A-I-L-L-E-U-R.