Most of those old Superman stories (and indeed, most of DC's stories at that time) were often written on the fly. The editor would draw a cover and then tell the artist to make a story based on that cover...you know, ones like "Superman's been exposed to Red Kryptonite, and now he's a gorilla!". Continuity wasn't even considered...they expected their readers to grow out of the material in a few years. One of the reasons that Marvel nabbed such a huge market share when they appeared was that they had a clean continuity (at that point, anyways) and consistency across the line. Characters talked about events in other comics, and it felt like a single world.
All of which is a long way to get to my point about Robin and X. As a detective and gadgeteer, Robin's equipment load-out is the most variable of the group. The thrown gadgets were all pretty consistent with equipment Robin's already used (note how Starfire looked at his broken Robin-rang which, when broken, looked like, you guessed it...a Red X). The trick was that Robin knew each of their vulnerabilities, and exploited them (but that trick didn't work twice, as we saw).
So all that really leaves us with is the holograms and the invisibility. The holograms were gadget based, and really required set-up to work. They weren't on-the-fly, and usually that's how the Titans operate. Mostly they were a convienent plot device, and I wouldn't be suprised if we see them once or twice more. But they require preparation to use.
So all that really leaves us with is invisibility...and the writers left us with lots of outs here, too. First, it might have been part of the X costume, so the limitation might have been there, for a start. Still you could easily argue that it could be put in his Robin outfit. Whatever device Robin used, though, it wasn't terribly efficient. X never goes invisible for more than a few moments, as far as we know. At no point in the episode do we see X go invisible for more than a minute, at best. Robin uses those precious seconds to their maximum, creating the illusion of teleportation. But it's only an illusion. Red X's illusion is all based on careful setup by Robin. Note how Robin doesn't use invisibility to evade Slade's robots....indicating it's a pretty limited trick.