Here it is.
If you have a doctrine kind of a mind you should preach from shorter passages.
If you have more an exegetical kind of a mind, you should preach from longer passages.
Neither is bad. Just different.
Most preachers in my circles are big passage guys. They are engineer types who glory in logic and structure. At college they felt more at home in OT and NT lectures than they did in systematic theology. In their preaching they have taken very naturally to a Stott type approach of preaching a passage from one end to the other. If an idea is not in the passage directly before them, they'll generally leave it out. They are big on context - but seeing the passage that they are preaching in the context of the book it comes from more so than seeing the passage in the context of the whole bible.
Most of my minister friends try to preach like this. But for some of them it is really unnatural. They read a verse and their minds jump to other parts of the bible. They find that a chain of logic doesn't make their hearts sing, and at the thought spending 20 minutes showing how 2 chapters of Matthew's gospel hang together perfectly... well they yawn.
In the old days of preaching from a 'text', guys like this were in their element. It came fairly naturally. I'm not suggesting we go back to that. Single verse, out of context, pious reflections... who wants that? But. What I think guys like this need to do is simply preach from shorter passages. Maybe just 8 verses instead of 30. Take the time. Explore them closely. Go on that excursion round the bible that you always want to go on. If you are only preaching a few verses it needn't detract from your big idea. Give us depth. Really apply it.