if you can hit a 40mm kill at 40, you can sink a 15mm at 10 yds... but i don't think a worlds course is right for uk conditions... but there are days and times where a smaller kill could be utilised to good effect, even if it's just to cheat the average.
We shot reducers at cgc as a single lane (we did 6 x 6 because we didn't string, then called a cease after each lane and reset)... that went out to 30-35yds with 15's to 25's... you'd be suprised how many lower grade shooters got 4+ with regular occurance...
but as ever, if it's to be done, it has to be done right. If you're of the opinion that at 25mm at 9 yds is just really a kit test, why not move it out a tad and make it smaller to make it a shooting test?
I'm sure rich has some stats of who hits and misses what reducers on swefta courses...
I'll see if doc has one for the worlds courses... might give an indication of the difficulty people had with some sizes at some distances... the 22yd 15m kneeler was about on the limit i reckon, but i've said for a while that you could have paired closer kneelers with reducers... say a 40mm kill at 20yds with a 25mm at 25 in the same lane...
as ever, it's not mandated, just another tool in the box for a bit of different flavour now and then.
BFTA/NSRA County Coach
CSFTA Chairman/BFTA Rep