If I may go off-topic, I wonder why the “Standford” spelling is such a common typo? Is there a linguistic reason for it, or is it some sort of infectious meme?
It's possible it's QWERTY-related as a sibling suggests, but there's also precedent for this specific kind of sound change in many dialects of English: /d/ is a stop consonant, which are commonly inserted in the middle of a nasal (/n/) and fricative (/f/), and in particular /d/ is produced with the tip of the tongue the same way that /n/ is, so it and /t/ (the unvoiced variant) are the most likely stop consonants to be inserted after /n/.
I mean typing it slowly, left ring finger 's', left pointer finger 't', left pinky 'a', right pointer 'n', then because 'f' and 'd' are so close on a qwerty keyboard any sloppiness between the left pointer and middle finger sitting on the 'd', 'f' would mean the d gets hit first as you roll into the 'f', seems pretty easy to make
