> Go codebases by non experts are peppered with magical incantation (sleeps, etc.) to avoid the dreaded "all goroutines are sleep".

I'm confused. This is indicative of a deadlock, where no goroutine can make progress. Sleeps would mask the symptoms, yes, but would never actually solve a deadlock, the program would just do nothing for a longer period of time. What Go codebase(s) are you referring to?

> A concurrent Go program will likely behave differently given 2 bits (just 2 lousy bits) of difference in the object binary. (runtime.GOMAXPROCS(1) vs runtime.GOMAXPROCS(2)). Imagine someone touching those 2 bits in a "large codebase". It is practically impossible to do the same thing in a large Java codebase and fundamentally change the programs runtime behavior. (Happens all the time in Go.)

If you are trying to find a low number of bits, you can just use 0. GOMAXPROCS can be set via an environment variable, the function is just to override that value.

More to the point, I am convinced that you are wrong. You are saying that in a Java class file, there are no 2 bits I could change that would impact the behaviour of a program, and that is plainly false.

> It is very difficult to reason about a Go routine's behavior in a "large codebase" without global view and a mental model of the dynamic system e.g. which go routine is doing what and who is blocking and who is not.

I guess this could be true if you engineer a system where every goroutine depends on every other goroutine. But it isn't true for code I've seen. As an example, the http library in Go has a goroutine that accepts TCP connections, and a goroutine for every accepted TCP connection. This knowledge is not necessary to use it, and is not necessary if a different part of your program is using it, because it is exposed behind an abstraction (http.Handler). To paraphrase the OP, Go enables simple programming. It doesn't forbid bad programming.

> There is nothing, absolutely nothing, that you can do in Go that you can not do via libraries in Java.

Depending on what you mean by "do", I believe Turing would have something to say on this matter: http://en.wikipedia.org/wiki/Turing_completeness

> On the other hand, there are plenty of things you can do in Java that are simply impossible to do in Go.

Depending on what you mean by "do", I either agree with you, or think you are mistaken. If you mean things that you can syntactically write down, like a Giraffe is-a Animal, or an Apple is-a Fruit, then yes, that is impossible to write down in Go. If you mean a problem that can be solved in Java that cannot be solved in Go, then I think you are mistaken.

> Once we factor in the possibility for bytecode engineering, then Java is simply in another higher league as far as language capabilities are concerned.

Why is this in another league? You can use assembly from Go, meaning you can generate code and jump to it if you really want to. Not sure why this would be considered a special feature of Java, or even why you think Java pioneered this. Bytecode is just a portable assembly, but its just as portable to build per-platform assembly emitters (like compilers do).

> Most people who rag on Java are clearly diletantes Java programmers.

Right. That makes sense to me; no one who knows anything about Java would ever criticize it. Sarcasm aside, this demonstrates a fallacy in reasoning.

> If Go actually manages to be as effective as Java for concurrent programming at some point in the future

It isn't more effective now? News to me.

> when they fix the somewhat broken runtime

Sorry, remind me what this is referring to?

> It just works. (But it is "boring" because it's not bling anymore. Oh well, kids will be kids.)

This is dangerous thinking. This is the cry that the native programmers raised when Java was born. Try and keep that in mind.