As I spend more time in Japan, I pick up habits that I'm not sure are good or bad. My question here is about nuance / occasion of usage.
In formal contexts, how does the impression differ between these two locutions:
I get that ~くない is the standard taught to 初級 students of Japanese and that くはない is something that appears later.
I'll throw in my guess: for me, 悪くはない sounds like making a judgment more so than 悪くない, but I'm not at all sure if that's right or if there's anything else it throws in. I also tend to add です for politeness at the end when using 辞書形 constructions in polite contexts so as written above both get the です thrown after.
In other words, I'm asking what sort of impression difference putting the は adds. Obviously you can say 悪くはありません as well. But mainly, I'm trying to understand how the two expressions might differ in nuance.