>What's the best I can get then?
>

Refox seems to be as good as any of the alternatives, and has some support. Not including debug information, encrypting, branding with ReFox and stripping the source from class libraries (clear the Methods column from the VCX, SCX, etc. - make sure to do this to copies, not the live librries, because once it's gone, it's GONE from that copy) and PACK after compilation but before building at least ensures that the comments and debugging details are gone. of course, that means you have to live without the debug information when appy fall down go boom...)

If someone is willing to go to the expense of buying several decompilers, you aren't going to beat them...you can piss them off, but determined thieves with the ethics of slime mold are going to get your code - the idea is to put them to enough expense in retrieving the code and then going through the commentless extract ends up costing more than paying for a legitimate copy of your code. If you wanted to go to the trouble of writing something, you can write something to plow through methods and convert local variable names into meaningless strings (something like find your LOCALs, and for each LOCAL in a function/procedure/method, replace the variable name with the return value of SYS(2015) - this means that you'l be SOL if things break, though...)

Or you can use the old SBT trick of abusing macro-expansion all over the place and make the code nearly indecipherable - with the realization that you'll be in the same situation, except you'll have that wealth of comments spread out in your code...