This is an attempt to ensure that the same code is called in the same way whether during developer testing, installation testing or production

It has no such benefit over the code I posted.

If anything, the fragility of your approach has the opposite effect of the one that's desired.

App::ipchgmon::run line, as that would mean moving the option parsing out of the modulino

You just said you wanted to use the same approach everywhere, so that's a good thing. The script calls run. The modulino calls run. You get the same code both ways.

But why are you using a modulino at all? You just said you wanted to always call the code in the same way. But making it a modulino does the exact opposite of that. It gives you two ways to use the module, and two ways of running the tool.

I'd prefer to change this to a simple link to the modulino

Why??? Hacks upon hacks for no benefit.