The act itself can be open but the true motive secret. Snowden's example of gerrymandering shows what he means, it's a practice ostensibly to balance voting districts but there is clearly a conspiracy to use it for political gain.

Define “in the open”.

Through lens of (social) media and through our own cognitive biases the idea of anything being done “in the open” seems more like self delusion.

You’ve never heard of an “open secret”?

but is it not 'conspiring' ?

it's not a 'secret conspiracy' sure, but it is a 'product of conspiring'; and x-acy is a linguistic construct for expressing 'product of x'