Well, it's very easy to fry the 2.5" cable as it provides power to the drive as well as carry the data. I'd imagine what happened was that it was connected wrongly - dangerously easy to do in an A1200 seeing as there are no guides surrounding the IDE port to ensure you line the pins up properly. I've seen it many times, sometimes it fries the drive, others it just fries the cable. I guess you got lucky.
The side the connector's on doesn't matter - ribbon cables and connectors are designed that way - once you get the pin 1 indicator right, it doesn't matter which side you put the connector on.
