What is it supposed to do?

Yep that's what it says on Impulse. It would be nice to slow enemy units as they try to escape the grav well with a starbase no matter what way they try to escape.

I never really liked the idea of it.  We have disabling abilities and I think some ship with a slow already and plus I wasn't a big fan of the fluff description of it.  Ships in gravwells aren't really manipulating subspace, but instead just using conventional chemical or ion drives, so some sort of subspace inhibitor seems silly from how I understand it.

Sorry, I think you have that backwards.  Ships moving in a gravity well ARE manipulating "subspace"; in Star Trek, the subspace drives were the sub-FTL movement drives for in-system travel, and presumably this game is using similar concepts.

The two reasons they can't be "conventional" drives:

> SPEED.  Under Newtonian movement, there's no such thing as a "top speed", until you get up to relativistic speeds; also, ships can't turn on a dime like we see them do.

> SCALE.  No matter how you cut it, 1g of acceleration isn't going to get you anywhere very quickly, especially if you want to be at rest at the end (say, if you're coming in to bomb the planet).

So basically, "subspace" refers to the way to move faster in normal space, while "phase space" is this game's hyperspace FTL method, also used for some weapons.  A Subspace Inhibitor, then, makes perfect sense as a device that slows down ships' normal movement.

As to why they'd leave it out of the game, I think it'd have some huge balance headaches.  Against the kind of players who charge in and blast away (or the AI), it'd do nothing, against people who like to make their enemies chase carriers it'd be crippling to one side...

Warp drives used subspace bubbles to have a ship travel at speeds that were physically impossible in normal space.  That's what I was referring to.  In-system travel was done by these:

http://memory-alpha.org/en/wiki/Impulse_drive

While they do use the word 'subspace' in the description, it seems to be more a case of technobabble than real explanation.  Regardless, I don't get the sense from the SINS manual that they're using standard propulsion significantly different than burning fuel and dumping it out the back in some manner.

Both these reasons fall under game design.  It's rather hard to have a ship system in place that allows infinite maximum velocity and incredibly slow acceleration for large ships without ending up with a broken and/or boring final product.  As for subspace and phase space, they presumably refer to the same thing.  They are both dipping out of the restrictions of regular space physics in order to accelerate and travel at faster speeds.

As for the Subspace Inhibitor, I was just expressing my dislike of its background info.  For gameplay reasons, they can say it works on Space Pony dust for all I care and that's fine as long as it adds a gameplay mechanic that is wise and useful.  Not seeing it in Entrenchment leads me to believe they either didn't have time for it, or didn't think it fit those gameplay criteria.

Ok thanks for clarifying that.  Can we expect any new utility structures in the next expansion backs?