Yes, I used to be an instructor - and a Chief Flying Instructor at one stage too. That was a real looooong time ago but, back then, it was common to talk about forces being in "equilibrium" in S+L flight. The only way this could be shown, during a blackboard/whyteboard briefing was via the 4-forces model.
Lift and Weight were equal to one another, so it readily made sense that they cancelled each other out. Thrust and Drag were clearly equal to one another and it therefore made sense that they, too, cancelled each other out.
Every student I trained in this concept understood the concept straight off. Indeed, after a few very carefully chosen words at the start of the discussion, the trainees would be telling ME how it all happened! I always love it when a plan comes together!
That provided the foundation upon which to build the briefing on "climbing", where you MUST have a "Total Resultant" vector - otherwise there is NO climb. Again, I could start the discussion with a few carefully chosen words and stand back to let the trainees tell me how it all happened.
And, ya know, the thing is that I'd learned it all in much the same way. I did smplify it. I really was easy to understand and, above all, it was also very easy to demonstrate in flight!
Well, that's my hand grenade into the topic, but it all worked very well over the 10 years that I spent as an instructor.