How does EIZO do 240Hz out of 120Hz?

The EIZO Foris FG2421 is marketed by Eizo as a “240Hz” monitor.  How is 240Hz accomplished out of simply repeating a 120Hz refresh without interpolation? There a good, valid scientific rationale:

1. First pass refresh is overdriven, done in total darkness (erases previous refresh).
2. Second pass refresh is clean, done in total darkness (erases overdriven refresh).
3. Strobe backlight flashes at end of second pass refresh (clean refresh seen by eyes).
Source: page 15 of EIZO FDF2405W manual, same method as EIZO FG2421.

So while the EIZO Foris FG2421 is doing black frame insertion via a LightBoost-style strobe backlight (white paper) strobing 120 times a second, it is creating cleaner and sharper LCD refreshes, for CRT motion clarity without VA overdrive/ghosting artifacts.

EDIT: Other reviews, including TFTCentral’s, reveals the FG2421 backlight does a sub-millisecond pre-flash on the first refresh, and a longer >2ms flash on the second refresh. This is a slight difference in strobe backlight behavior relative to EIZO’s FDF2405W.