In reply to Deadeye:
To make the problem clearer:
Ground is at 0
I can reach up to (say) 2.25m
Branch top is at 4m and bottom at 3.75m
Ring is 0.25 diameter and I want the base at 2.5m up.
If I do the maillon trick (like a retrievable abseil), the highest I can tie off the ring is the top at 2.25 and bottom at 2m - too low.
I can make one ring ok by putting the adjustable daisy inthe system at half length (so I can reach the end of the tape to pull it shorter.) That gets me to base of one ring at about 2.3. But I can't do the other one.
And carting chairs, ladders, cherry pickers, a mates shoulders, tame Griffons, hovver packs, or the like, isn't the answer.