EH-Net

I recall having seen something quite a while ago about the use of debug.exe to recreate an executable.  A text file is downloaded to a locked down system, renamed as a .bat then run.  Towards the end of the batch file there are a series of commands such as:

@echo rcx >> tmp1
@echo n >> tmp1
@echo w >> tmp1
@echo q >> tmp1
@debug < tmp1 > nul
@copy /b /y tmp1 tmp1.exe

The main body of the text file has the representation of the executable which is piped in sequence into tmp1.  I am interested to know how the executable is converted into the format that can be used in a text file in this way.

I don't know if this technique is used currently in pen tests or if it's been superceded by other techniques.

Thanks in advance.

I've been researching and it seems that exe2bat.exe does the job of converting an executable to a format that can be used to recreate it on a target system.

Is this technique of value in the pen testing field now or is it redundant?