You were smokin' something.
No model of Honda Insight has included a power cord. However, you are correct to say its engine can't always keep the batteries charged. Honda's hybrid design (Insight and Civic) differs from Toyota's in many fundamental ways.
One key difference is that the Prius has _two_ motor generators, allowing the engine to recharge the battery with MG1 at the same time it is using MG2 to help drive the vehicle. This means the batteries don't get drained, even when driving uphill for long durations. Few Prius drivers have ever seen the "turtle", and most occurrences have been caused by cold weather conditions.
The Honda design has only a single motor generator, which means it cannot recharge its batteries while it is providing electrical boost. So, continual acceleration conditions can drain the battery, leaving the car to finish climbing the hill with only its gas engine.
Honda drivers who have switched to the Prius initially complain about the battery icon on the multi-display, because it only has 4 bars and doesn't show much detail. (The Honda displays have 10 bars on the battery icon--the same as on their gas gauge.) However, they quickly realize it is not necessary to watch the Prius battery icon, because it never goes down, it just alternates between 3/4 and 1/2. When driving a Honda hybrid, you have to watch this gauge constantly, so that you know when to slow down and drive less aggressively to prevent loss of electrical assist.
Douglas (2002 Silver, Wisconsin)