...it can't be denied that knowing the basics of the language you develop in of prime importance.
It is important, that is why I agree that IDE's should not be used when first learning a language. But my point was certain IDE's can, if you truly want to learn, help you learn common method signatures, what commonly used methods do. They will only help beginners if the user actually types everything out themselves, instead of using code completion, code generation et cetera.
I am pretty sure none of us would want to hire someone who is completely lost without an IDE; after all, it's a Java developer we are looking for and not just a Eclipse/Netbeans/IntelliJ user.
Which is what happens when beginners are incorrectly taught to always use and IDE (which is why they should not use them), instead of using it when they are ready.