I get your point, that this is probably enough. Since, the chances of an attacker having a nearly identical address is close to none. However, I personally always check each letter/digit. This is just a habit I've developed, since if you are taking the responsibility of being your own bank, you should probably consider the weight of that. Unfortunately,  because of our culture, and the fact we've started to rely on banks for many years now, we've become acquainted with short cuts, and getting other third parties to assure everything is correct. This develops complacency, which I believe is one of the biggest threats to anyone's security, no matter who you are. In fact, its probably more dangerous as you become more confident, and assured with Bitcoin, since that's basically how complacency works. In the beginning you are probably checking every letter/digit, and your heart is pumping the first time you send that transaction, and check it on the Blockchain to make sure it actually was sent correctly. Then, once you develop a confidence, you start checking less, and less as its a time sink.

However, wallets don't have a built in function to protect you from complacency. Well, they kind of do; some will prompt you whether you mean to send it to x address, but as we are human, and are already susceptible to complacency, most will just click okay without actually checking anything.