Hi David:
Stephen Covey (7 Habits guy) says "seek first to understand, then be undestood". As this applies to instructional delivey, we may have a message, a pint to make. We can state it and move on. Or, we could ask a question and participate in a discussion, and apply the reponses to the ubject matter. Our personality in conveying information should be to facilitate thought, rather than giving it. We can't be too over the top as students will recognize insincerity. and we can't downply our role as facilitator.
Being confident about what we know demonstrates competence, and that delivery approach usually gets ad keeps the students attention.
Regards, Barry