I suspect these two goofs felt comfy with CNTs only because they already knew all this stuff was (literally) not going to fly in the 2000s. In these the 2020s, Jensen instead has figured upon anhydrous silica with no "Griffith flaws" (per Copilot). This is a cable we should be able to spin from Lunar regolith and ship up to space for cheaper. Let's see what this buys us.
Jensen was targeting 13.8 GPa of pure laboratory SiO2 so ρ = 2.2. The deltaV equation √(13.8*2/2.2) = 3.54 km/s. That'll get you to Hohmann for any porkchop of Mars - or for Venus (2.8 km/s); but the next-good Byrnes-Longuski cycler to Mars is "6S9" which is terrible.
If we could stationkeep a tether-hook at STL1, this would work for a faster cycler to/from Venus: the 2L4. Venus herself could not use a 13.8 GPa cable. Both of us can however run the 3-0-2-9 cycler - in the 3.4+ km/s range on either side - and then we can keep both tethers in high-orbit.
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