Sorry Skires, though you were a 'Squire' my mistake
I haven't looked at a single-point at any depth purely because it seemed like it wouldn't be going anywhere rule wise, but even with the sling 'kept' in one position on the arm it is easy to vary the tension by using an adjustable swivel on the rifle end as I do already for the Ching sling.
This way it's possible to have two positions one for sitting and one for kneeling which can be adjusted in seconds from the rifle end. You really want to keep the arm end of the sling consistent.
If I get a chance, I'll take some shots showing the use of both single point and Ching slings in different positions.
I for one would like to see this debated in an informed manner preferably to show the benefit that proper use of a sling can bring to a FT shooters ability.