First you learn to crawl, then you learn to walk, then you learn to run (then you learn to drive five miles to the place where you like to walk or run).
The same process applies to learning about split infinitives, with just as much crashing into walls and falling on your butt. First you learn that you've been doing something wrong, then you learn that it wasn't wrong in the first place, then you learn that your initial grasp of why it's not wrong was in fact wrong.
For those of you on deadline for your blogs or eager to turn to the horoscopes, here's the must-know stuff about the dreaded split infinitive: Don't worry about it. Ninety-nine out of 100 language authorities agree there's nothing wrong with it. So if your energy for learning grammar is limited, this one does not belong on your priority list.