As an avid consumer of Western Buddhism, this is pretty standard understanding. Concentration and insight, another complementary aspect of practice, like the dichotomy between sitting alone and sitting in a group, or between a steady daily practice and a deep intense retreat.

The linear story is that increased awareness of focus teaches the sitter that there are no real borders in reality, it is a seamless whole, and as the sitting continues, awareness naturally opens up to include the full current moment - seeing thoughts as thoughts, emotions as emotions, sore knees as sore knees, twitchy neighbor as a twitchy neighbor, etc thru the myriad things all showing the way, bright and clear.

But they are mutually reinforcing partners that appear as distinct.