Well here is what I have done. I took a plant that was 29 days old and topped it.
Here is a picture of the plant where I topped at. It was at section 3. The plant was 29 days old, 7 inches tall with 7 total nodes. I cut the top two nodes so that it was left with 5. Notice the newer sprouts growth through the following pictures.
Here is what the plant looked like 9 hours after being topped.
Another pic at 9 hours
Here is a picture of the same plant 4 days old
Here is a current pic of the plant 8 days after being topped
Another pic at 8 days
Plant is now 37 days old, 8 inches tall and 9 inches wide. By topping the plant the lower growth is receiving more light. Also, the plant now has two stems to grow further nodes out of, instead of just one. This in theory should produce more candidates for clones, and more places to produce buds if you decide to flower.