It is precisely as the Apostle Paul said in 1 Corinthians 13:1. Though writers may write with the pens of men and angels, if we have not clarity, we will have a hard time paying the rent. Paul said something like that, anyhow.
True, "clarity" is not a writer's only goal. If our purpose is to write poetry, "clarity" may scarcely be a goal at all. In the realms of prose composition, clarity ordinarily comes first. We positively hunger to be understood. Assuming this is our goal, how do we get there?
For one thing, we could begin by distinguishing "since" and "because." You will perceive at once that nothing of cosmic dimension is under discussion here today. We're talking peeves and crotchets. Every writer has a drawer full of such stylistic foibles.
Interruption! Did you know that a foible is "the part of a sword or foil blade between the middle and point"? Remarkable! You could look it up. I thought a foible was something by Aesop.
Thus we turn to an editorial in The New York Times in July. The piece dealt with a rumored schism within the AFL-CIO. It began, "Since we live in an era when the chasm between the lower and upper classes is growing, it's hard to imagine that working people," etc. Would "Because we live in an era" have been better? I believe so.
The problem is that although "since" can function causally, its first meaning is temporal. As adverb, preposition or conjunction, "since" instantly conveys a sense of time passing: With "since," we propel a reader from then to now. Thus, "It's been a long time since Lucy wrote." Or, "Since he arrived, we've all been drinking gin."
I stumbled over that sentence in the Times because my eye coupled the "since" to the "when" and to the present-tense "is growing." The misunderstanding lasted no more than a nanosecond, but such nanoseconds are important. They tend to accumulate. This particular nanosecond could have been avoided by a homespun "because," i.e., "Because we live in an era when the chasm is growing ..." Nanoseconds in prose are like billions in a federal deficit. A flicker here or a billion there, and pretty soon they add up to a real problem.
Consider a similar modifying phrase from another Times editorial, this one in April. The topic was Iraq's new Cabinet: "While Mr. Allawi will not be in the new Cabinet, one of his least appealing rivals, Ahmad Chalabi, will." Would "Although Mr. Allawi will not be" have been better? Again, I believe so.