aluminum vs steel flywheel for stroker

I ran a 340 in a '64 Barracuda that was mildly built and included an aluminum flywheel. It worked great. A friend talked me into changing it for a heavier flywheel, telling me it would maintain better RPM on shifts. So, being young and dumb I changed it out. The car had little noticable difference on idle and no difference on takeoff but it felt like an absolute slug when cruising along and mashing the accelerator. It did also decelarated more slowly. I put up with it for a couple of months and swapped it back to the aluminum. Then the guy who recommended the steel flywheel to me bought it for a Dart he was building at a nice discount. (maybe his motive to get me to buy a steel one in the first place:-))
I never had that car at the track but it sure felt a lot snappier with the aluminum flywheel compared to the steel one!
And it would beat his Dart with the heavier flywheel when he got it together too!!!