Yes...but...

Dear ??? (SD90),

Sure, a "staging balloon loop" could certainly work as described...
(you might even consider using a "one way turnout" loop as shown here

...however, many modellers find the actual switching of industrial spurs fun,
and the room required for even a "ultra minimum radii" balloon-loop could well hold an _actual_ fun switching area...
(If the idea is that "the balloon loop simulates the industrial park in less-space",
it might not actually end up being as much of  a space-saving as one might first think...)

Happy Modelling,
Aim to Improve,
Prof Klyzlr

No loop needed.

For an industrial area it wouldn’t be unprototypical to not have a runaround available, so the train might come back out with the engine on the same end it went it with.  So you don’t even necessarily need the loop.

I’m doing basically the reverse.  I have a single track leading into the industrial area that will be my entire layout.  The end the connects to the main line and the entire rest of the railroad is off scene.

I guess it all depends on your personal preferences which end of the industrial area lead you think the operating interest lies on 

Staging

A loop is a large footprint, you can do almost the same thing with a couple staging tracks.  You can even restage between sessions by shoving the cut out of staging track #1 and putting it on the cut in staging track #2, then shove staging track #1 back in.  Next session run inbound into track #2 and put the engine on staging track #1.  That rotates cuts by a session at the cost of moving some cars around between sessions.

One way turnout

Prof Klyzlr, thanks for your excellent instructions  http://www.geocities.ws/loggingloco1/dctramway/points.htm on how to construct a one way turnout. I have a large grain terminal that utilizes a number of spring switches that work most of the time. However they require constant fiddling to keep the tension correct or remove a stray bit of ballast or whatever. Like you, I wanted foolproof operation. Thanks again. 

Single track/spur staging

Thank you

Thanks for your comments, I do have 3 existing industrial areas already, in addition to an auto compound (takes 14 autos on 2 tracks), an IMS terminal (takes 20 cars on 2 tracks) and a large industrial complex (takes 34 cars). In all, there are close to 100 cars at industrial spots, I'm just looking for more ideas as I'm just about out of room. I love operations, and I'm always looking for new ideas.

Michael Good.

Maybe

Maybe I don't need a reverse loop, a hidden straight track would be 6' long, enough to hold a switcher job, not to mention much easier to build and no auto reverse module to buy!

"I'm wondering if anyone has

   Many folks have used off scene industries in some form. Hidden reverse loops or staging tracks of other configurations could be used to simulate off scene industries. The cars could be blocked in the correct order for the various industries then shoved off stage to get picked up next session. It would be a way to add more operations without much extra construction. If you had multiple staging tracks one of them could be defined as the industrial lead and the rest saved for other purposes. I have a visible yard that serves as multiple destinations and locations on my layout, it's purpose depends on what railroad's train is going or coming and from or to what direction......DaveB