That’s always the risk with regression based analysis and predictions. Past trends are never guaranteed to always continue into the future. And one of the most often times when big paradigm shifts occur to totally throw off past trend lines is at times if inflection. The Type100 and this new design represents uncharted waters for the PLA, where for the first time in its history it’s not the one playing catch up to the world.
Which neatly brings us up to one of the fundamental challenges the PLA would have faced in this contest as de facto world leader - just what are the requirements and CONOPs of future armoured warfare? It no longer has the luxury of being able to copy everyone else’s homework in terms of detailed performance requirements and instead needed to also work out what the grand vision of how future armoured warfare should work.
If you do not have a clear and well defined vision of what future armoured combat might look like, the obvious solution is to pose that question to the field in the first instance and see what the troops and market comes back with. A truly blank sheet design again reminiscent of how the PLAAF 6th gen development was rumoured to have went.
I guess this shows the fundamental difference in how we view the PLAAF 6th gen competition. While you seem to think the PLAAF went to both SAC and CAC with separate, radically different yet fully detailed design specifications to meet predetermined CONOPs, I think the PLAAF started with a far more open scope of asking both teams how they think future air combat will evolve and produce a design to dominate in that envisaged future combat doctrine.
The wildly divergent weight class and intended performance priorities are from underlying philosophical differences in how the two teams expect future air combat is expected to evolve instead of them being aimed at different niches in a well defined combat environment.
That in turn was why CAC was so ecstatic about the the outcome of the May 7th air battle, as it validated their overall vision, which was far more important and consequential than just the J10 proving its own intrinsic capabilities.
I think this is a common problem people have with China watching in general where they mistake discipline for a lack of ability, ambition and vision, with a hint of the old classic trope of China being a hyper-controlled state where decisions always flow top-down.
Modern China would not exist as it is today if that was the case.
Also, this fundamental different philosophy is not as unprecedented as you seem to think. Just look at the Chinese UAV industry as an example of the frankly bewildering diversity and often apparent significant overlaps between various designs.
As with the UAV industry, China owns the overwhelming majority of the high value capital stocks of development and production of tanks and armoured vehicles, so it can make those capital stocks available to promising private sector pitches to make sure barriers to entry do not allow the market to stagnate. How else do you think they managed to get so much innovation from just one proper tank making factory in the whole country?
Another common mistake to make is in thinking all procurement processes work the same way for the PLA. There will be procurements where the PLA knows exactly what it was and will issue detailed design specs that need to be met, and in such cases they generally want that need met ASAP, which is the kind of tenders we are most exposed to. But there will also be other, more open (both in terms of timeframe and design specifications) routes where a particularly interesting and/or promising design and/or designer emerges from the frankly ridiculous number of competitions and contests that takes place annually in China, and resources are made available to see what might come if it. Often, the most interesting and revolutionary designs comes out of this second route, and these also tend to be the ones most kept under wraps by the PLA.
In theory it's not "impossible" that the PLA has departed from the usual way in which most military forces (including leading military forces today) carry out developments of projects, and I'm fairly open minded about the PLA being able to surprise us with either new methods of doing things or pushing technological boundaries that we previously didn't expect for them.
But the idea of the PLA fully funding competing CONOPs and products intended to operate within CONOPs would be not only a more inefficient and risky way of doing project development --- but more importantly it also doesn't provide a more convincing or explanatory answer than "they are intended to be complementary from the outset" to both Type 100 and the heavier MBT existing (or J-36 and J-XDS both existing).
I suppose if we had some sort of grapevine rumours suggesting that Type 100 and the heavier MBT were a result of being competitors at the CONOPs level (or J-36 and J-XDS being competitors at the CONOPs level) then we would have reason to seriously consider such a prospect and greatly re-evaluate the way that the PLA has chosen to develop these big ticket items.
But as it stands, the most straight forward and logical answer to me is "they were intended to be complementary in the same unified CONOPs to begin with". It is the most reasonable null hypothesis, and we'd need a fair bit of corroborating indicators to seriously consider overturning it imo.
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The wide variety of PRC UAV designs is actually a great example of why it is irrelevant to the Type 100 and heavy MBT (or J-36 and J-XDS) relationship, because the vast majority of PRC UAV designs are company/institute led efforts rather than projects being commissioned by the PLA at the outset, with many aiming for export customers. Same goes for the wide variety of PRC AFVs (including MBTs) and ground systems which are aimed for export. Of course, sometimes certain industry led projects or export oriented projects find themselves procured for PLA use, but that is typically within the bounds of an established PLA CONOPs or system of systems or doctrine.
And sometimes there are new types of systems (like high end UAVs/UCAVs) where the PLA will buy some to evaluate which types are best suited for their requirements as part of the CONOPs refining process (such as the many CCA types we've seen that we know are in IOT&E, of which most may end up in service but some may end up being discarded).
In the case of Type 100 and this heavy MBT (as well as J-36 and J-XDS), to our knowledge are not industry led efforts, but are genuine article PLA led projects, for a PLA requirement that should already have had a CONOPs well defined before embarking on the very expensive process of developing a couple of new generation medium and heavy MBTs (or a couple of new generation heavy tactical fighter aircraft).
And if we want to entertain the idea of them being a reflection of original competing CONOPs that have led to competing prototypes as well... then I think we need some indicators/rumours to suggest it first.
