The way I use it is basically is to describe a kind of a schelling point, or a focal point, where the game (by game I mean incentives and consequences) changes after making a decision on which path to take. Why I wanted this term vs just using cross roads is how illustrative the term "Commited" is to what happens next. Its like a "minor" point-of-no-return, that the game changes but not so much as change your entire strategy.
One real useful use for the term is when I talk about social engineering or dealing with people in a social setting. There are "Favors/Debts", and there are "Pushes", "Soft/Hard sells", as well as "Conditioning" and other engineering type terms to illustrate the strategies one has to employ to deal with social constraints but one part that was hard to describe was "Committed Phase" meaning:
I'm always looking to make friends, I believe we change and that friends help us with their advice and perspective and having a lot of friends who are willing to give their TIME and perspective is always very valuable. Now when you bring certain elements into a relationship, you change it: you are enter a "Committed Phase" where your friendship is still one that is friendship but some of the elements have changed.
The classic example is lending money to friends. Its always advised never to bring up such matters around friends because it changes the relationship. ( Dan Arielly explores it in Predictably Irrational, but I forget the specifics of the page and chapter). This is an example of a "Committed Phase" and it applies to other actions that change the landscape of the relationship or "Game"(as in the game theory definition of Game).
You can imagine that when you're talking to people and you express a hesitation to "ask this person out", then that is an example of a "Committed Phase". Or when you propose to a change of relationship, as well as realizing the validity or importance of Ambiguity (actions which have motives that cannot be easily discern or Impossible to discern).
In RPGs, the GM or the Players later on learn a more "realistic" scenario has many more "commited phases" that you cannot just retry or just attempting something, success or not, changes the game. So if you had to break down your strategies you can use CP (committed phase) to describe a list of possible consequences and consequences for even trying or even considering.
Its a great term to think about especially in light of Thought Police or where there is are limits even in the mind. That considering to do an action is already punishable, even if it was just considered and there was no action that took place.
You also then realize "Ambiguous" Actions, like certain kinds of "Flirting" which is permissible socially but can be interpreted as something or nothing at all. The need for "hinting" may be one of those tactics which tends to fall in "Alls fair in..." or in various situations where it is very hard to prove a particular "intention". If you've grappled with the Legal implications/challenges with Intent you get the picture of how this is a really big array of options and possibilities.
Anyway, Happy Holidays!