And too much superstition is bad for yours. I smell the stink of a certain wannabe aeronautical engineer on you. What you (and he) missed was that counting surfaces is not how RCS is determined. You (rather he) have also failed to show that if there is an increase in the RCS as a result of the canards and the strakes relative to a configuration with horizontal stabilizers, that this increase is tactically significant.
Actually, regarding the highlighted --
IT IS.
There are three rules, or guidelines, on designing a low radar observable body.
Control of:
- Quantity of radiators.
- Array of radiators
- Modes of radiation
The sphere is the ideal 'stealth' body because it is the most obedient to those three rules. In fact, the sphere is the ideal radar calibration body.
http://www.centurymetalspinning.com/radar-calibration-spheres/
https://en.wikipedia.org/wiki/Lincoln_Calibration_Sphere_1
In radar detection, everything is a radiator. If a structure can reflect a radar signal, it is a radiator.
The sphere has only one radiator -- its body.
Whereas, with something like this...
You can see multiple protrusions from the main body -- the fuselage.
So regarding rule 1, the higher the count of structures that protrudes from the body, the greater the contribution to total RCS. The problem then become how to minimize that contribution. You can apply radar absorbent materials ( RAM ) but that does not take away from the fact that the structure is a contributor.
Rule 2 -- Array of radiators -- is how the canards are in relation to nearby structures. Whether their relationship is tactically significant or not, we do not know unless the jet is under independent RCS measurement testing and the data is available for all to see. But the problem remains in that the higher the quantity of radiators ( Rule 1 ), the greater the difficulty in applying Rule 2. Not impossible, but greater difficulty.
Rule 3 -- Modes of radiation -- is how radar signals leave a finite structure. In learning about radar principles, students are taught using theoretical infinite surfaces. But that is not real life where everything is finite. A radar signal make contact with a structure. Sooner or later, it has to leave that structure. The higher the count of finite structures, the greater the relationships of these structures in Rule 2, which could lead to higher total RCS.
The point here is that no rule is more important than the other. All three have equal significance.
So if you think that the J-20's eight major protrusions/structures have no bearing on final RCS, we are indeed talking about 'Chinese physics'.