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I can't think of anybody that did, but I can think of someone that I'd love them to: Orbital !!

First one comes to mind is John Askew, he came back with a great decent album.
I'm gonna be shot for this but Tiesto has been doing a great job lately with his Remixes if he was ever gone i would consider that a strong come back.
Side Note: To some of us a producer is on or off the radar is usually based on getting or not getting heavy ASOT support.

Aly & Fila fell into the loop that everyone who used to like them feared, actually most uplifting trance producers are in a one big loop first sign is that they all use the same sound packages, vsts ,plugins and shop from the same place Andy Blueman, Aly & Fila Nitrous oxide and most if not all the famous producers for making uplifting trance are raping these packs till they got stuck in one style and can't come up with anything different or new either because their skills are very limited or that's as far as producing could ever go for them.

Cosmic gate did a fail come back their album completely flopped despite the "Support" they tried to get from big radio shows it couldn't save them.

Cosmic Gate & Martin Roth.

And no one else.

I think we should try and make sure that we're not talking about Follow-Ups. Come-backs are mainly returns of artists that disappeared for a while. Follow-Ups are more of singles/releases to previous smash hits.

The ones that failed miserably are Binary Finary.