At the start, 1 canister has the target. 9 are dummies. All are prepared and sealed in front of all participants and taped closed. The canisters are randomly numbered - but no one now nows which contains the target.
During the test the canisters are then randomly chosen to be placed on the test area (or at 10 different locations).
The randomising team records the number (1-10) of the canister and the order/location (a-j) it is taken to the test site.
The testee team records which in the order/location (a-j) that edge says the target is under.
So. One team knows the order in which the targets were placed in the test area and the other team knows the order/location that edge chose as the target in each trial. But no one knows if he's been successful or not.
At the end, you just open the canisters, 1-10, and find out which number canister the target was in. Let's say it was no.4.
Using the randomising team's record you can then say what position/order the canister was placed for each trial, e.g.,
Trial number / target position
1 e
2 j
3 b
4 c
etc
Using the testee's record you can indicate edge's dowsed choices
Trial number / target position
1 c
2 e
3 b
4 d
etc
In this case he got a hit only on trial 3.
My way's blinder
Nope - just me being pedantic.