I have often thought it made it seem like the intent was no warp drive - and yet the damn thing has engines resembling the Enterprise.
Not exactly, the nacelles of the Romulan Bird of Prey had stern openings reminiscent of exhaust nozzles with no visible patches, markings or whatever at the body's stern to suggest another propulsion system there... (which was probably intentional).
According to "Metamorphosis" they scanned for antimatter residue (assuming this shuttlecraft had exploded) which they - most fortunately - didn't find. This tells us they expected antimatter to be onboard.
If I'm not mistaken that would also explain the trail of light left as a signal by the Galileo 7
to attract Enterprise's
attention: antimatter particles annihiliating matter particles and resulting in photon emissions.
(of course, the sparking gamma radiation would have caught Enterprise's
attention, too, but TV audiences may not have been able to understand such "technobabble"