I agree. I don’t know why converting ST to FT would be an advantage. Perhaps that’s not what’s happening, even if they think it is?
For instance, that protocol wouldn’t produce near-peak lactate. It may be higher than aerobic threshold (~2 mM), perhaps even higher than ~4 mM or MLSS. But it would still be a mostly aerobic effort.
To maximize lactate production, you need to use longer, passive rests. Something like 8-10x 8-12″ with 2-3′ passive rests will show peak lactate values. In a weekly progression, this type of workout also increases anaerobic capacity.
The short rest periods in the protocol in the NCBI article won’t allow the FT fibers to recover, so I don’t think high lactate values would be observed. Although very intense, this seems like an aerobic protocol to me.