Question: I can't really tell what someone means when he says "you could do worse than [x]." [Live example](https://stackoverflow.com/questions/2058247/successor-of-msxsl-exe):

> 
> If you are just interested in a simple command line processor which uses MSXML 6 then you could do worse than using a simple JScript application.
> 
> 
> 

Does anyone know what, exactly, he is trying to say? What nuance is he trying to convey?

Answer: 
This is an example of *litotes*, which is stating a positive through a negative. It just means that [X] is not bad, that there are many alternatives that are worse.

In the sentence you link to

> 
> If you are just interested in a simple command line processor which uses MSXML 6 then you could do worse than using a simple JScript application.
> 
> 
> 

the person who responded is suggesting that using a simple JScript application is a good choice.
It's a indirect compliment. You can go check out this link => <http://www.english-test.net/forum/ftopic24532.html> for more explanations.