No it doesn't. Keep reading that thread.
It does. Is the reason gmaxwell wrote not related to security?
so that an attacker who has complete control of your network (and thus can prevent you from hearing the longest chain from the honest bitcoin network) from putting you on a fake (low difficulty) isolated chain unless they can also trick you into running replaced software. With the checkpoints such an attacker hast to have a ton of mining power in order to continue the chain.
Based on this information, will you change your post to "not all checkpoints are evil"?