I wrote my first Step Four in 1993. I have written a number of Step Fours since then. I wrote a major Step Four last April, then another one on a particular area in around October. Step Ten seems, in the Book, to suggest adjusting the steering wheel as I am going through the day. Step Eleven seems, in the Book, to suggest reviewing the ups and downs of the day. If I've got serious s**t going on, I do a Step Four as laid out on 64 et seq.
I tend to do a 'comprehensive' Step Four once a year plus ad hoc ones if Ten and Eleven do not clear the trouble. My ego is powerful and, at times, not amenable to the steering-wheel adjustment of Step Ten or the wrist-slapping and sock-pulling-up of Step Eleven. It needs a thermonuclear detonation of Step Four plus multiple Step Fives, total surrender in Six and Seven and a round of amends to bring me back to a state of grace where Ten and Eleven become, once more, sufficient.
Some people say that, if you do your Step Four properly, you never need to do another one again. That has not been true for me. My first Step Four, in 1993, did not address, in advance, what my ego managed to do with entirely new situations that arose in 2010. Other people may not have an ego that creeps up and spreads its roots deep DESPITE a diligent approach to Ten, Eleven, and Twelve, but mine does. Perhaps I have a nastier ego. Who knows? All I'm interested in is what works to keep me well.