Talk about dumbing it down...this measures a sermon by the amount of verbiage. The sermon on the Mount is pretty short if I remember correctly. Sometimes all it takes is a well spoken sentence that speaks to the head and heart.
I do not agree with your criteria...getting Bible for the week...much of what long winded pastors tend to say is more their opinion than the gospel. A good short sermon is much more difficult to write than a long one.
After 48 years of preaching -- and retired for a few now -- I can say that my longer sermons were often too convoluted to comprehend. Speak a few words, speak to the heart, and give the Holy Spirit some credit for comprehension and ergo, conversion.