WNW: Where'd It Come From? Back-formation

One of my favorite quirks of English is how versatile it is in creating new words, and often without us even realizing it.
A common way of creating new words is essentially tweaking a current word in a process called back-formation.
With back-formation, the new word usually looks like it is the original one and that the other word or words came from it.
That idea make sense grammatically, because we tend to just slide into creating back-formations. The new word is typically shorter, because...