Holding down backspace on iPhone Holding down backspace on iPhone deletes about six characters per second. 

However, after about three consecutive seconds of holding down backspace, entire words start disappearing by the pair at a rate of about three pairs per second!

How can I disable the "feature" that starts chomping two words at a time a few times per second when holding down backspace on my iPhone? 

iOS 7.1.2, iPhone 5s
There is no way to disable the fast delete. There is an undo command, however, for when you've deleted too much. When the keyboard is up, shake the phone. A popup asks if you want to undo.