How is restricting max throttle to max continuous power--which was NOT max throttle IRL--more realistic? You're asking for an artificial limitation be imposed based on a PROCEDURAL rather than PHYSICAL limitation. Personally, I'd LOVE it if planes that used injection for WEP could run out permanently with no recharge (excluding rearms: ground techs refilling the tanks while they gas up your plane). Because that's a PHYSICAL limitation of the aircraft, not an arbitrary one based on what some technician decided "If you exceed this, your crew chief will tear you a new one while he strips down the engine to check for problems."
Incidentally, I checked the charts in the manual and WEP is altitude specific. It lists 57.3" at SL, 59" at 12,500ft, and 59.5" at 17,000ft. I tested offline and the F4U-1A does hit these marks at the indicated altitudes, so the E6B chart is a bit misleading as it doesn't account for current altitude.