Redundancy can actually be useful in notation as a sort of error-detecting code. In this case, if the pitch-symbol and pitch-position don't match up, someone must have made a mistake in transcribing it.
Whether it helps one when reading music is another matter. I remember learning to play an electric organ as a youngster with a book of sheet music that came with the organ; being aimed at beginners, each note head had the note letter written inside it. Hummingbird is basically using the same idea, just replacing the letter with a symbol. It probably does make it easier to learn. Whether it would be of any use for an experienced musician, I kind of doubt. (I certainly outgrew expecting the note head to contain the note letter, myself.)
Whether it helps one when reading music is another matter. I remember learning to play an electric organ as a youngster with a book of sheet music that came with the organ; being aimed at beginners, each note head had the note letter written inside it. Hummingbird is basically using the same idea, just replacing the letter with a symbol. It probably does make it easier to learn. Whether it would be of any use for an experienced musician, I kind of doubt. (I certainly outgrew expecting the note head to contain the note letter, myself.)