Simultaneous Modifiers

“Be sure the introductory phrase can be accomplished at the same time as the action in the rest of the sentence,” Kathy Ide says in Proofreading Secrets of Best-Selling Authors. She gives an example: “Hugging the postman, Delilah ripped open the box.” Delilah couldn’t open the box while hugging the postman.
This is one mistake well-known authors sometimes make.

Some great words from False Memory by Dean Koontz:

Standing at a huge sheet of glass in the dark, basking in the incoming radiance, gazing at this urban sprawl that lay before him like the biggest playset in the world, he knew how God would feel, looking down on Creation, if there had been a god. The doctor was a player, not a believer.

What we might see for an improved version:

Standing at the floor-to-ceiling window, the doctor peered into the darkness and the urban sprawl of radiant lights. With its white and red streaks of traffic on the roads and the twinkle from the windows of tall office buildings, he had the perfect view of the biggest playset in the world. At that moment, he shared the feeling God would have when looking down on his creation—if there were a god. But then, he was just a player on this stage, not a believer.

Some logic for making improvements:

1. With the introductory participial phrase, we need to be sure the ongoing action of the phrase coincides in the place and duration of the action of the sentence. The introductory phrase in this paragraph works fine, since the doctor is standing for all the time he’s looking out the window, but it’s not equal in duration with his knowing. We can keep it as long as we change the main verb to to peering so they are the same in duration.
2. “Basking in the incoming radiance” is something the doctor experienced as a part of the viewing and precedes the knowing, so it’s a small problem as well. We do better with showing what the basking looked like by describing the city’s night lights.
3. “Gazing at this urban sprawl” is a third introductory participial phrase, which is concurrent with viewing, not with knowing.
4. The “huge sheet of glass” is a floor-to-ceiling window, not a mirror or a room divider. So we do better to describe the window, not say it’s a sheet of glass.
5. Three introductory phrases is too many. We might use two where necessary, but a single introductory phrase is best because we don’t want too much delay in seeing the picture that is made most relevant by the subject of the sentence.
6. “Him” and “he” in the first sentence don’t require an antecedent because we know he’s the point-of-view character. In the last sentence, “he” was replaced by “doctor” to avoid confusion with the possible misassignment of God as the antecedent. If the pronoun was good at the beginning of the paragraph, ideally it should be good for the entire paragraph. We can tighten the focus by making “doctor” the subject in the first sentence instead of the pronoun.