you dont understand. you not need to set executable to script. you can execute shell, or perl, or python, whatever with option reading and executing script command from file. its same what operating system does when executing your script file if it have executable flag and shebang line (#!/bin/sh i.e.).

for example:
you have /home/user/MyDocs/script.shyou cant set chmod +x as usual, but you always can launch shell with your scriptin this way your script dont need to be executable.