no you can't use it without JAVA , the self-contained installer you link contain an offline install of JAVA and install it.
I posted that installer. What you say is true. The primary purpose of the self-contained installer is to solve system Java installation and update issues. The self-contained installer completely eliminates all those problems, but it does not eliminate Java per se.
We've had some debate here (at my company) about the security of such installations. The general belief here is that they're OK. The Java is not being installed as a system service (as you say, it is "offline"), and is only really available to the program that it's packaged with. If you can point me to real information that suggests otherwise, I'd like to see it. I am by no means a Java expert.
Here's a fun fact: any application you install could use an embedded Java install like this and you'll never know it unless you go digging.
Bottom line: I personally would feel completely comfortable using a packaged Java app like the one I posted. It is far down on the list of things most likely to cause me problems on my PC. You can make your own choice.