Hello...
I understand now. Present Perfect tense is used to describe an action or life experienced that happens in the past and still continuing to the present.
In my humble opinion, yes, that's the one of the purposes of Present Perfect Tense.
Example; We've been discussing it for several times. It means we had discussed it before and probably until today. Am I right?
Sorry for saying this, but I think you made mistake here, because you used Past Perfect Tense (We HAD discussed...) which is something different from Present Perfect. Likewise, I would not use in this case Present Pefect Continuous, because it refers that you didnt cease the action started in the past at all, which in your case doesn't have a sense to me. Instead of that, if I were you I would cling to "simple" Present Perfect.
It has been discussed since Monday afternoon. It means we've discussed it recently and possibly until now. Am I correct in my sentences?