Here's a New Year's thought: Short sentences in work telephone calls telegraph that you're busy and in demand, not blagging, faking it, or kicking about the gaff aimlessly in your military boots.
You can tell people are just fannying at their desks, justifying their existences, as they use long, rambling lyrics that repeat and say sod all.
Forget agents as positioning devices, just use short sentences and the rest will follow. Fact. Roger. Done.
For phones, for work, short is good. Get in, get out and fuck off.
The reverse is of course true for lunch convo's.