I think you’re misunderstanding things. FTA: “If you use the standard bitmap icon formats, you’ll probably store them in their own files, separate from the fil

I think you’re misunderstanding things. FTA: “If you use the standard bitmap icon formats, you’ll probably store them in their own files, separate from the files that use them.” ⇒ i think they’re talking of having to read the same data again and again, and then try to minimize the number of blocks read from disk. Of course, reading the icons again and again is the MVP implementation, but not necessary. They could create a cache of icons. Even if they don’t, the file system cache would significantly decrease the number of actual disk reads.