Yeah, that is a pretty sound theory. For anyone who doesn't know, in the deleted scenes and comics from the movie, the Narada is first disabled by George Kirk's suicide attack, then apprehended by a large Klingon fleet who have been monitoring their border - Nero is taken to Rura Penthe and incarcerated, and the Narada is placed in a parking orbit above - Nero then escapes years later, regaining his ship (which I guess was being studied by the Klingons).
While I'm here, and because I love pictures of starships, lets have a look at some Romulan ships from over the years:
^ This ship is a non-canonical one from the Star Trek: Chronology that was used to represent an early Romulan vessel - I've always liked it, as it looks primative like the SS Valiant
^ The earliest canonical Romulan ship; or rather a modification of an early type of warbird, this vessel was altered from a retired class, possibly with the addition of those antennae
^ This bird-of-prey was the first bona fide Romulan warship that Earth encounters, during it's first contact with the Romulans, and presumably the main combat vessel of the Romulan War
^ By Kirk's time, a more modern bird-of-prey had replaced the Romulan War era one; many species had adopted a grey-white duranium style of hull plating, including the Klingons and Federation
^ Conjectural image of what Romulan ships may have looked like during the Motion Picture era, where we unfortunately have no examples contemporary to the Miranda and K't'inga
^ During their short strategic alliance, in which the Romulan Star Empire and Klingon Empire briefly became a single anti-Federation bloc, the Romulans adopted the Klingon D7
^ The next time the Federation encountered the Romulans was after a long period of isolation, and they were stunned by Romulan progress, which unlike the Klingons, had kept pace with Starfleet
^ Possibly in response to the trend toward faster and leaner ships during the Dominion War, the latest design of Romulan warbird was smaller than the behemoth D'Deridex class