I don't know if you could hide it from competition - it can be unminified ex with: http://jsbeautifier.org/ I have tried this before and it worked.
if you use Closure Compiler in Advanced mode it will rename and rescope pretty much everything except native methods and strings (making lots of globals cause it assumes you're compiling all page's code at once), it will eliminate unused code even from third party libs like jquery and do all sorts of stuff that make the beautified code very expensive to understand, follow and reverse and even then you may end up with only half a library that does only one specific task and the rest of the code would be missing.
you have to do a bit of JSDoc annotations in some places to fix some breakages and restructure the code a tiny bit to get it to rename absolutely everything but the results are excellent.
To have that sort of optimisation you'll have to run the Closure compiler with ADVANCED_OPTIMIZATIONS enabled. Last time I checked that mode of compilation didn't work with JQuery and not with most other libraries. To use it with your own code you'll have to follow certain rules.
I think most people just use uglify or the Closure compiler in SIMPLE_OPTIMIZATIONS, neither of which does the very advanced stuff of ADVANCED_OPTIMIZATIONS.
All you will get is a lot of function a with arguments z d and f calling eq on z and passing it d, then returning the qln value of the result.
Slightly more readable, yes, but still like debugging assembler.
even so, there's nothing it can do to bring back eliminated code, meaningfully extract inlined functions and scope everything appropriately to help a reverser understand context. it would still take an immense amount of effort only to get back something very specific.
the only thing you can probably get out of it is some largely mathematical chunks that cannot be restructured much, eg: rgbToHsv.
There is a lot to minification, these tools just undo cosmetic minification.
If it can infer most of it from OSS? Sure. But big web apps do a lot more.