When I am shooting trap with my flint 20 bore with the choke, I use a Track lubed wad between power and shot with a thin overshot wad to top it off.
I have shot trap with it, using only thin B (over shot) wads, 2 between the powder and shot and one over, with no lube and had no difficulties loading
and shooting 20 shots.
Patterns with the thin "B" wads only, is almost as good as the lubed wad in my choked tube. If non-choked, the thin wads can give very good patterns
better than most other combinations. The only way to find out with YOUR gun, is to try different combinations.
What was the "jingle"? Less powder, more lead, shoots far, kills dead?
My load is usually 3 drams of 2F, 1 1/8oz shot in my choked 20 Bore.