DrJynx86answered grow question 4 years ago Amazing LST!
This is something I have learnt from my agro engineer father.
Plant stems stretch by the ends, so in this case for example, the (2) stem won't get higher than it's now, but the lateral stems that will grow from there will definitely stretch at least double that arrow marker.
The end of the stem (1st picture) will at least stretch from the middle (middle finger nail) to the point. If you keep that stem parallel to ground, your plant will only grow horizontally and not stretch vertically at all.
Keep on the great care!
happy smokes!