I think I'm calling the "move from camp 1 to camp 2" and the "happy tussle" abstractions only because we witness both from such a great distance and both are free of dialogue/ silent. Though, granted, there are many, many poignant silent moments in BBM.
That said, the feeling of happiness I get from the "move from camp 1 to camp 2" scene is particularly abstract. For me it hinges on the quality of light, the tone of the music and probably most specifically the sound of the bird call. In a way, the happiness I perceive here is based on elements of the scene that don't hinge primarily on the activities of Ennis or Jack... but I project my happiness that I find in these things (music, light, bird) onto Ennis and Jack. This is what I mean by abstract here... although the word might not be exactly accurate. It's most definitely subjective and personal.
I'd say that the sensation of happiness in relation to the "happy tussle" is significantly less "abstract." But, something about the complete silence and the distance we have on the boys makes it very surreal to me. But definitely happy.
Again, these are just entirely my own, personal impressions.