I agree, and i think that if rome hadn't risen the greeks would have recognised the possibilities of steam, paticularly in Ptolemaic egypt eg. Abdraxus' machines of alexandria, and don't forget that greeks made the Antikytera machanism (a quite accurate mechanical calender/astonomical thinger-ma-jig, i think but i can't really remember)...
infact i think the theory is that it was a roman collecter of greekish things that it was destined for before it ended up on the sea bed..imagine if it was a wealthy well connected roman who saw the potential of mechanical constructs..