Thank you, Mr. Webster. Unfortunately, that doesn't help clear anything up for me because this sentence...
...is as clear as mud as written.
double negative: dou·ble neg·a·tive / (noun) 1) a negative statement containing two negative elements (for example didn't say nothing ); 2) a positive statement in which two negative elements are used to produce the positive force, usually for some particular rhetorical effect (for example there is not nothing to worry about!)
Exactly this. I'm glad I'm not the only one lost in translation.