[ced]

You're a native speaker, right? Can you really see a new character and be confident about your guess? I usually think "This is probably a Zhi, but it might be a Ji, too, or something else entirely." Granted, some characters, like animals, are easier.

[cglee]

Yes, native Chinese speaker, though English is my best language. I think you can guess based on context as well. Not precise as you'd like, but not a blank slate either.