"a telling reflection" is a correct and usable phrase in written English.
You can use it when referring to an insight that is particularly revealing or insightful. For example, "The manager's comment was a telling reflection on the team's morale."
September 30 2015 "Memoir," Libby York's most recent recording, is a telling reflection of a gifted and experienced singer whose subtle manner may have kept her from greater popular acclaim.
But the fact that Ms Le Pen has put politics and her quest for power before family is a telling reflection of how different she is to her father.
Among the western liberal democracies, only the United States stood partly aside from the chorus of condemnation - its muddled response a telling reflection of its own contentious anti-terrorist war.
They're purely comic creations and stripped of any pathos; they're somehow not human enough to be really funny -- neither unexpectedly bonkers nor a telling reflection of life in the world of the sane.
The Newark Teen Arts Festival, as part of Youth Art Month, is a celebration of students' views of their world as well as a telling reflection of the talent that thrives in the public school system.
In a telling reflection of their growing influence and reach, the national news shows sponsored by CBS and NBC had recently expanded their nightly broadcasts from fifteen to thirty minutes.
We might think of games as charming historical artifacts, but they are also telling reflections of social values and mores.
Yet the pictures to which American audiences are flocking this summer offer equally telling reflections on the state of the nation, questioning strong-arm strategies and probing the acute self-doubt they can produce.
These reflections gave a telling description of the patients' functional ability, life circumstances, and resources for or obstacles to managing symptoms and illnesses, that the physicians could follow up.
The Korean genre-jumble "Nowhere to Hide" has so much visual stylization and so many high-velocity lifts -- from film noir, Hong Kong action films, Expressionist painting, music video and, as far as I can tell, reflections on puddles -- that it's out to create a new genre: a film that wants only to excite itself.
We've had something like between 18 and 30 attempts - even 4-1 doesn't probably tell a true reflection of the game.
