no, he's not. i don't understand why people have a hard time understanding the logic of it. yes, 60i is 30 frames interlaced. But that's not what he is always saying. He is always saying that 60i and 30p are essentially the same, which is a different statement entirely, and is also entirely incorrect.
Imagine if you were shooting with two cameras side by side, one is 30p and one is 60i: 30p is progressive, which means it records the whole image at once. it records a whole image in one instant, then a whole one in the next. Whereas interlaced records half the image when the other camera records a whole image. HOWEVER, between the first and second progressive frames, the interlaced camera records another half frame, meaning it is recording image data that the progressive camera isn't. It records the same amount of information total, yes, but it records information twice as often. Really isn't a hard concept to understand. Sorry if I'm coming off as a dick but I'm getting so fucking tired of people saying that 60i is the same as 30p. It's not.
And I do know how to handle footage, the comparison you made doesn't really make sense. of course 30p slow motion in fcp would probably look better than 60p slow motion in imovie. it's a completely different level of motion estimation. i guarantee if you shot 30p and 60p with the same camera, you can get smoother slow motion out of 60p if you slow them both down in final cut. Sure 30p might look fine at 80%, but compare the two at 55% and tell me which one is smoother.