You may be interested in Hilary Doyle's take on the subject. https://youtu.be/UuLx-bzKjaQ?t=199 (About 3:20 in)

There were two units equipped with Elefants. One did very well, the other, not so much. It came down to how you used it, much like every other piece of equipment used by any military force anywhere.

Bear in mind that the steppes of Russia was one of the few places where Ferdinand was really well suited, and the unit reporting the kills also had Pz III, SuG III and StuPz IVs all of which could knock out enemy tanks too.

Now, given that the situation was ideal for a vehicle of Ferdinand's characteristics, one can see how it ended up with such a high kill/loss ratio, but that's just a snapshot taken during the 'happy time'. You could look at U-Boat kills/losses in 1941 and extrapolate from there as well, despite the fact that U-Boats were having a pretty lousy time of it by the end of the war.

Now, let's look at Ferdi from a larger perspective.

Wiki says 83 Ferdinands were sent to Kursk. Battle began 5th July. Doyle/Spielberger/Jentz reports 37 operational on 7th July, 26 on the 8th, 13 on 9 July. In the entire battle, only 19 vehicles became total losses, which leaves nearly fifty vehicles down for repair on average. That's half the force deadlined.

Some reports from the line units, again taken from D/J/S's "Heavy Jagdpanzer"

"Since the Ferdinand guns, as well as the Sturmpanzer, show remarkably many technical weaknesses, it was forseen that this type of armored vehicle should be withdrawn for 2 to 3 days after 3-5 days of action, and for longer periods after longer action, in order to get them back into technical order. The workshops have worked day and night to repair the breakdowns, so that enough vehicles move against the enemy. Through the excessive technical demands on all the vehicles - because of the tactical situation-, they all really ought to be overhauled every 14-20 days. The technical condition is now thus, that daily the cases increase in which repaired vehicles on their way from the workshop to the troops break down with new or other technical defects. Only such vehicles can be reckoned on for action against the enemy as have survived the trip back to the front after being repaired. I therefore report to the Pz AOK2 that in the shortest possible time my Regiment will, for technical reasons, not be ready for action, if it cannot be made possible to give all vehicles at least one week of time for thorough repairs. "

Also...

"With an average of 15 kills per vehicle, one may well speak of success. It must, to be sure, be stressed that the stated figure could be much higher today. Unfortunately, the greater part of all vehicles is almost always being repaired. This condition, moreover, worsens from day to day, because with the growing wear of all parts, the supply of spare parts, much too short in any case, is used up."

And... "The transport of the 42 available Ferdinands will cause difficulties, since apparently the obtaining of the necessary Syms wagons will cause difficulties..." (And then a lamentation on the lack of rail transport capability, special railroad cars required).

So, Ferdinand, yet again is an example of the German emphasis on the battlefield effect without due consideration of everything else which goes into a properly balanced AFV design.

Ferdinand was master of the Kursk battlefield... but only if you brought enough that you could afford to lose half of them in repair (and enough mechanics to repair them all), the enemy was nice enough to give you time to recover and repair them, and you had the ability to get both the vehicles and the spare parts, if you thought about building any (remember, Ferdinand was making use of hulls from a failed Tiger concept) to wherever the battle happened to be.

So, no, I don't think it's fair to say it's evidence of German armoured superiority, it's merely evidence that the Germans chose to build really tough, hard-hitting vehicles which came with their own unique problems that their opponents didn't have to concern themselves with.

As an aside, I just published an article from a Soviet paper about Ferdinand's first action. It was written so soon after the battle of Kursk that they had still not associated the names of the vehicles correctly. http://worldoftanks.com/en/news/pc-browser/21/The_Chieftains_Hatch_RedStar2/

The Soviet takeaway was "These things are tough, but we can kill them"

I'd argue that the Elefant's super-high KD ratio is a result of the Germans fighting a defensive war from mid-'43 onward, and as such a lot of them were doing their work from static, prepared decisions under cover. Pretty optimal conditions for tank destroyers/SPG's.

Additionally, less than 100 were built, with another 500 or so Jadgpanthers coming in behind them; essentially the same vehicle but tweaked/upgraded in certain areas. With such small production numbers, it's hard to conduct a really accurate quantitative analysis, and the numbers from Kursk should probably be taken with a grain of salt anyway.

The Elefant was just another big, heavy, complex German Wunderwaffe. I think the two pieces of equipment that the fans of German armor should really be talking upStuG III variants and Pz. IV's. Both were workhorses that were produced in very large numbers (well, for the Germans), remained relevant until the very close of the war, and served as the basis for a lot of specialty variants.