I don't know about reviewing it - but I saw the original production on tour in, I think, 1954 (the year of first publication, according to the slightly revised Faber paperback first edition of 1957, which i have just found in an Oxfam shop, showing signs of some reading at least) or (more likely) 1955 in Manchester, with at least one original star lead, Margaret Leighton, for whom Eliot had contrived a full-spotlight first entrance, of which she took full advantage, still in the cast.
Eliot had by then publicly acknowledged its source in the Ion of Euripides. In a way it's an essay in the West End theatrical conventions of its time into which he consciously but - High Tory that he was, without any declared subversive intent - sought to inject the the strengths of the classical theatre, while increasingly working within what he conceived to be the range of audience expectation. The producer of the first run, E Martin Browne, seems to have been his eager supporter in this view. Curiously, 'The Confidential Clerk' set out on its provincial tour in the wake of 'Waiting for Godot', which imposed its own conventions, as did the surge of English theatre of the fifties and sixties which followed it. 'The Family Reunion', which when new must have impressed West End folk as high-falutin, ironically may have been a better start in the long run, and not the false one Eliot seems to have thought it.
Looking at 'The Confidential Clerk' now, discounting its surface theatricality, and trying to see it as a study in self-deception, Eliot's solution, fundamentally that folk should be true to their own instincts about their identities and hold their ambitions up to the light before acting on them, seems a trifle simplistic - and if you were a sixth-former when the play was first performed in 1953 emphatically so. But it might just have more interest than we might think. Even its homages to West End convention are pasted on to another 'family reunion', which however schematically if closes the play, ends with very conventional, actorish, questions about something which is far from conventional. Possum had not retired.