Interesting rumor...
The word "moderate" tells me that the 5D4 will have 24mp. This makes sense to keep buffer capacity, FPS and speeds decent. Also, helps with low light capability. Moderate is a term used to describe when something isn't so great as you'd think.
The word "leap" for dynamic range tells me that rather than the dismal 11ish stops, this camera will probably hit high 12's or low 13's. Which is a leap. A full stop is that is. That's significant by any measure, and for Canon they'd consider that huge. Still not as good as Sony/Nikon. BUT...looking at the earliest 80D results, it appears that Canon is "tuning" their dynamic range like Sony/Nikon. Very high at ISO 100 - 400, about equal to other sensors at 800-1600, then about 1/2 stop weaker beyond 1600....
Which isn't a bad formula for a sensor. After all, once you get into the ISO 3200 and on...the dynamic range stinks in general and saving it a 1/2 stop doesn't do anything to give the image the same pop that low ISO's have.
Like Sony, the big DR numbers drop really fast. Canon sensors have had a more flatter trajectory for DR across the ISO range. Doing better at higher ISO. The counter argument to my earlier dismissive attitude toward high ISO DR is that at higher ISO's - every little bit helps when you are on the very edge of "usable" photos. You want anything you can get. It is of course, a case of diminishing returns.
Same ISO has 1DX2 doesn't say a whole lot. Just means what you can set will be the same, but the 1DX2 will certainly be cleaner.
Anyway, this camera being geared toward video is a disappointing rumor. But has validity. While I and many others would want a killer stills camera that sacrifices nothing for video - Canon not long ago put out what they believe to be the ultimate stills camera the 5DS. This liberates the 5D4 to be more video centric. Whatever the case may be, at 24MP with new sensor, more DR and higher ISO - this will serve as a great low light events camera for wedding pros and general purpose pro use.
I also think that the lack of examinable RAW files for the 1DX2 has everything to do with the 5D4 and its rumors. It has been repeatedly rumored that the 5D4 won't be announced until he 1DX2 is shipping well. This is to slow down defections to Nikon at the non-flagship level. Also to help protect pre-order sales. Here's the reasoning. The 1DX2's image quality will be better than the 5D4 with the exception of all-out resolution by a little bit, and only in ideal situations like studio at lower ISO. Much the same as how the 1DX was better than the 5D3, except in pixel peeping studio shots or heavy crops at low ISO. At higher ISO, the megapixel advantage disappears entirely.
When people see and examine the 1DX2's image quality, dynamic range and ISO -- IF they are not satisfied with that - which I am almost certain **some** people will not be, they can easily infer that the 5D4 will be worse, and thus make a decision to move on if they see fit.
The idea here is that they don't want the 5D4 being prejudged by the results of the 1DX2 for as long as possible, and keep it as close to release time as they can. While information on the internet moves quickly - it still isn't instant and months do make a big difference. Sometimes it takes many weeks or months for someone to get around to having the time to dig in some online research and read all the nit-picking, pixel-peeping fanatical blogs that split hairs between sensors and brands. Not everyone makes camera technology their hobby and follows rumor forums. I'd say that type of person is a very tiny minority. Thus, the general buyers will take longer to get that info or results.
Example, if I was really interested in high dynamic range ...and I took at look at the 1DX2 and found that it doesn't best say, the Nikon D750 or whatever...that would be a big turn off to buying the 5D4, as it is unimaginable that Canon would have the 5D series camera best the 1D in that regard.
Overall though, I do think Canon will make sure the 5D4 is a decent all-around pro DSLR, regardless of what video features it has. For those heavily invested in the Canon system, such as event shooters like wedding pros - this will be their go-to camera. They don't obsess about dynamic range or a few extra megapixels. It is smart move to gear toward video..there's just too many out there who love to use FF as a video platform for the low noise and great IQ. For the wealthy enthusiast, gear lovers and tech junkies, those not too invested in a system -- unless Canon puts up Nikon numbers on DR, there will be a lot more defections to Nikon in this one realm. Just figure, Nikon is due for the D820 not too far from now. The D750, despite the recalls, offers a tremendous amount of features and specs for an extremely reasonable price. That ties into my previous point, if the 5D4's sensor doesn't match or beat the D750's performance -- this will cause Canon to take a lot of abuse online because the D750 is running about $2k from authorized major retailers, an the 5D4 will likely debut at well over $3k....
