Coupling of pri and sec in 100:1 CST?

[cupoftea]

Hi,
We are doing a 100:1 CST using E20/10/6 former and core.
Attached A and B shows the 100 primary turns. C and D show two different ways of doing the secondary.
Please can you conform that C and D have the same coupling as each other, between pri and sec?

Also, the attached showing the two torroid pictures, please confirm they are both exactly one turn primary?

 

[Warpspeed]

Each pass through the hole counts as one full turn (primary or secondary).
What happens with lead placement outside the hole is irrelevant.

 

[Easy peasy]

To maximise coupling - have the toroid as small as possible while allowing the through conductor ...