McDevitt has a number of stories showing his interest in the potential for computers to simulate the human mind: "The Candidate" and "Combinations" both feature artificial recreations of historical figures and "Henry James, This One's For You" tells of a computer programmer who creates an AI writer that is so talented that the POV character (an editor) fears for the sanctity of the classical authors. I'm personally skeptical of the ease at which AI intelligence can be created and McDevitt shies away from or glosses over the ethical and philosophical implications. "Date with Destiny"--described by McDevitt as "'a situation that usually would lead to violence'" but ends non-violently--indeed finds a peaceful solution but it rests on a dictator wanting to seem like a peace-loving leader, which I think is rather unrealistic.
"Lighthouse", written with Michael Shara, was about an astronomer who discovered a way to detect just about ALL brown dwarfs (the method is a bit sketchy, since interstellar gas is known to redshift and block certain wavelengths) and finds that around 2000 of them are artificial. It had some strengths but it seemed to rest on this one idea and withheld it unnecessarily to the end.
Some of the weaker stories are:
"Nothing Ever Happens in Rock City" about SETI discovering extraterrestrial intelligence but told from the perspective of an unreliable narrator and far too short to be interesting
"Whistle" about a signal from M-82 that turns out to be music. Somehow the narrator is certain that, because the galaxy has a tenfold increase in star formation that the "sky is on fire" at the source of the music
"Ignition" takes place in a post-flood world where a theocratic elite governs ideas. Some people find a statue of Jefferson and when it's destroyed by authorities, a civil war is implied. Again, I would have liked to seen more, and as it stood this was an incomplete tale.
"Valkyrie" a naively anti-war piece where valkyries are actual entities... not really scifi.
"The Mission" a confusing narrative that takes place in the South after a horrible plague and people decide to scrap a rocket to survive...
However, McDevitt shined the most when he dealt with space exploration--or settings that involved a spacefaring humanity:
"Windows" is about a thirteen year old who wants to go to space but robotic missions are preferred over manned ones (just like today!). The character development went at a good pace but the story was a bit too short.
"The Far Shore" is about a character marooned on a habitable planet and spends his time listening to radio broadcasts from Earth 200 years prior which, by sheer coincidence, allows him to follow along on the events of World War II. He is rescued just before the end of the war comes to him. The story was good, but the final line was just stupid.
"Melville on Iapetus" and especially the two Novellas "In the Tower" and "The Big Downtown" were the strongest pieces. In all of them, alien artifacts are found; the Novellas also have strong detective aspects, which play out well.
It's these last three that give me an appreciation of McDevitt. I haven't read any of his novels, but if his strength is in longer pieces than I may just do so.