Alexa Capra | Dogs and More - The bow posture, an invitation to play?

Years ago I read an article on the existence of meta-communication in dogs. The example was the bow. In the bow posture, the dog bends his front paws resting them on the ground, staying with his rear raised. According to several authors this posture is a meta-communication signal as it changes the meaning of the behaviors that precede and follow the bow. The bow means "what I've done before or what I will do after is not serious, it's a game."
Searching “meta-communication signals” through Google, I just found an article that I dedicated to this behavior, many years ago.

When I started studying dogs during free interactions in socialization classes, however, I discovered that the bow posture was often associated with imposing behavior.

To impose means to claim to be stronger, to have the power to influence the behavior of another. In dogs this can be translated as a check on the movement of the antagonist. The dog may stop or move the opponent.
What I see are dogs that use the bow to stop, and to move another dog.

Are the dogs really just playing?

My guess is that the bow is indeed a play behavior, but it is especially frequently used when two dogs that do not know each other well use the game to define their levels of strength. One dog performs the bow, and the other moves or remains stationary. It is never random. The strongest dog moves on its own and does not get moved.
When the bow posture is to move the other, it is generally done with legs wide apart, while in the play bow, the legs are parallel. If the dog is tense during the bow, the top line of the body is a straight line, if the dog is relaxed, the top line forms an S-curve
The bow may be accompanied by a bark, and even a growl-bark.
Often we can see two dogs exhibit the bow at the same time, as if mirroring one another. If the action is quite intense, the bow is followed by a leap forward, and the dogs can collide, in an impact that can test their physical strength. And finally the bow can also anticipate an attack, the dog spring-loads before launching forward, physically overwhelming the opponent.