ASX Today, page-39761

Greenbushes got 72.5 % recovery in 2022 with a more complex process flowsheet:

https://fintel.io/doc/sec-albemarle-corp-915913-ex961-2023-february-15-19403-3937

"Greenbushes currently has two ore crushing facilities (CR1 and CR2) and three ore processing plants which include a technical grade plant (TGP), chemical grade plant-1 (CGP1) and chemical grade plant-2 (CGP2) with a nominal capacity of 4.5 Mt/y of pegmatite feed to produce a nominal 1.3 Mt/y of spodumene concentrate from all three plants combined. TGP is a relatively small plant that processes approximately 350,000 t/y of ore at an average grade of about 3.8% Li2O and produces about 150,000 t of spodumene concentrate products. TGP produces a variety of product grades identified as SC7.2, SC6.8, SC5.5 and SC5.0. During 2022 TGP processed (Table 14-2) 370,893 t of ore at an average grade of 3.94% Li2O and recovered 72.5% of the contained lithium into six separate products (SC7.2-Standard, SC7.2-Premium, SC6.8, SC6.5, SC6.0 and SC5.0).CGP1 and CGP2 process spodumene ore into lithium concentrates containing a minimum of 6% Li2O and a maximum iron content of 1% iron oxide (Fe2O3). The process flowsheets utilized by both CGP1 and CGP2 are similar and include the following major unit operations to produce chemical grade spodumene concentrates:
•Crushing
•Grinding and classification
•Heavy media separation
•Wet high intensity magnetic separation (WHIMS)
•Coarse mineral flotation
•Regrinding
•Regrind coarse mineral flotation
•Fine mineral flotation
•Concentrate filtration
•Final tailings thickening and storage at the tailing storage facility."

Any geologist/mining metallurgist will tell you that crushing/grinding with metal balls/components will add iron to the ore. The subsequent use of magnetic methods (WHIMS in this case) will make some ore to be lost with the magnetic fraction, due to the adhered metal. Given the exceptional grades at Greenbushes, they are able to produce the best SC concentrates even if they lose some ore with the WHIMS.
A process flowsheet that does not include ballmilling will increase the ore fraction that goes through the following steps (flotation).

So yes, 78 % is possible. And any recovery close to that will be excellent.