Actually I don't agree with you John. In real printing the lines are also not equal on each page. Widows and orphans have a real value with regards to the easiness of reading.
I find the solution of Arios with a special clause for long paragraphs actually quite elegant. I would not put it in a <div> though, but just say <p class="lpara">. In that case it would inherit everything from the <p> class, except for the things mentioned in the lpara class.