I'd say the reason for why the tut is done in such a way where the blades cycle up a lot faster than in the real world would most definitely be rendering times. If you'd do all the frames for a full 45 second animation like that with the dust and smoke particle fx it would freeze up your computer for an extra week or so. This would have been even worse a few years back when this tutorial was made, rendering in mental ray at this point in time was not nearly as fast as it is today and you'd use alternative rendering engines instead a lot of the time for your test renders, simply for the reason of speed and hardware limitations. This is still commonly done, you substitute indirect illumination and materials for test rendering at a higher speed in Maya Software. Also it's not that often when you watch a movie that 45 seconds is spent on getting helicopter blades up to speed on the screen if you think about it, even if it would be inaccurate
I think that animation is great for someone who's fairly new to Maya. Well done for completing the project, it would have taken a huge effort and I think most people give up. You got the hand held cameras pretty close to perfect, the heat exhaust works really well and all the elements that this should have are there.
The main critique I have on this would be on the particle effects for the smoke and the composite of the helicopter for how it doesn't quite fit in with the lighting in the environment. I think the whole scene needs to be a bit brighter than it is atm to work as that kind of environment. Both these things are incredibly difficult to get right though, probably the most difficult things in the whole tutorial. I think if you keep going like this you will be like Kari Brown with a bit of more time spent in Maya, as you mentioned you need to get better with dynamics but it's just a question of practice and getting simulations like this to look great is something that is really difficult to do. The fact that you modeled the complete helicopter is also very impressive, a lot of people get frustrated with hs modeling because it does come down to time, tiny details and accuracy so I understand how exhausted you'd be once you had the model done. Leave it for now and come back to this scene some time later when you've had a chance to recover and learn some more, this is already really good work