You know, I like some "roundabout" in a sentence, if it fits the character, and when I first draft, I have a lot of longer sentences with a lot of roundaboutation. I'm not the writer you go to for terse, just the facts sentences. :) But... but character-revealing voice-ian roundaboutation might be acceptable, but confusing verbosity is not. Hence:
He was just as glad he had to duck into the alley to get back to the mews where he assumed was the door she had identified as the rendezvous place in the note.
The "he was just as glad" is the roundabout stuff I want to keep. (It really helps, when you're trimming, to identify precisely what you want to keep. Trim the rest. :) When you have a voice that allows for more fulsome sentences, more elaborate constructions, that doesn't meant it's open season on adding junk into a sentence. In fact, the rest of the sentence should be as trim as possible, so that desired roundabout stands out.
Fortunately, I always put in plenty of junk that can be trimmed. To wit:
He was just as glad to duck into the alley to get back to the door her note had identified as the rendezvous.
So I let myself keep "just as glad". The rest was trimmable! And everytime I look at this sentence, I find more places to trim. :) So, I'm sure, can you, but tell you what-- instead of revising MY sentence (that is my job!), take a moment and choose a sentence of your own and revise THAT. (Put in comments and tell us what you did! So we want the before and after. We're mean that way. :)
Now I'm not trying to eliminate every word that might not need to be there. I want to keep the setting in there in almost every sentence-- that is, I want to keep the characters interacting with the environment-- so while otherwise I might delete the alley, I won't here. (In fact, I might make it the "dark alley" or the "gloomy alley." So there. I am such a slut. :)
But once I decided to trim, I realize that "rendezvous" sort of implied place.
Also that he really wanted to get back to the door, so who needs 1) the alley, 2) the mews, AND 3) the door? In one sentence? Alley, yes (because the previous sentence has him on the Strand, a big street), but mews? Why, other than to show that I know what a mews is? If I truly want the muse, I should make this two sentences, alley to mews, mews to door.
One problem I have, and I see in a lot of submissions, is trying to put too many actions (I mean, little actions) into one sentence. Nothing wrong with two sentences with two actions each and some transition in between. In fact, that will likely lead to more supple narration.
1. Trim redundant words.
2. Trim excess and "understood" actions.
3. Look for relative clauses and see if you can reduce them.
What's a relative clause? Well, it's a clause (has a subject and verb), and usually begins with a "wh" word (which and who are the most common), and performs as an adjective (modifying a noun).
Question: Do you need the relative clause? Do you need that thought even?
There are two relative clauses here, probably two too many! What, you say? There's only one "wh" word in there! Well, the other is "elliptical." That means it's there in meaning but taken out, just by custom:
He was just as glad he had to duck into the alley to get back to the mews where he assumed was the door (which) she had identified as the rendezvous place in the note.
Relative clauses are by nature interruptive, and because they are clauses (subject and verb), often feel more weighty than the meaning they impart. I think in conversation we often use them to mark time while we think of something else, or add some information we forgot to say. ("So John, who is my ex, called last night and wanted to go out.") When they show up in our written prose, they can often be trimmed outright (the "he assumed") or reduced ("she had identified").
I noticed that the "she had identified" was really clunky, and that "in the note" was misplaced at the end of the sentence. It was hard to figure out where to put "in the note" and "as the rendezvous" as they both go with the same verb (identified)-- what's first? what's second? Hey, whenever there's a conflict (in a sentence, not in the plot), punt! Prepositional phrases are (like relative clauses) adjectival, modifying a noun, and they're often reducible. Notice that I reduced "in the note" to make it actually the subject == the note identified... But then I thought I'd lost the "she" and the sense that it was her action, so I made it "her note" rather than just "the note." "She" is in there now, but in fewer words.
Anyway, I kept what I wanted to keep, but refined the sentence so that it's less verbose and thus less likely to attract the gentle attentions of the editor.
So everyone go out into your own work, and give us a "before and after" sentence, and tell us why you revised as you did, and what worked for you. And if you tell us you don't have any sentences that need trimming, we'll all hate you, so... just don't. :)