Yeah, I know what you mean.
The best explanation I've read of the PLB system is Doug's description in the PLB Test report on ETS.org. The link is
http://www.equipped.org/406_beacon_test_background.htm#How - scroll down about 1/3 of the way to the How COSPAS-SARSAT System Works.
Without a GPS the PLB system uses the Doppler effect to get a position.
Picture yourself hanging out your car window while driving at a moderate speed past someone blowing a loud whistle. As you approach the whistle will sound higher pitched than it will once you've passed it. Its pretty likely that you could signal at the point when the pitch changes and fairly accurately identify the whisle's location, at least relative to the entire car ride. The LEO (Low Earth Orbit) satellites do the same thing.
If the 406 MHz beacon doesn't contain GPS location information, It can take the LEO satellites up to 90 minutes for a satellite to pass by the source of the signal, which is when the Doppler effect can be heard and a location determined. The maximum time to Doppler location decreases as you move away from the equator, so in the 48 states it will take less than an hour to get a Dopplier location. The Dopplier accuracy is about 1.5 miles.
On the other hand, GEO satellites can almost instantly receive the 406 MHz beacon with GPS location information since they are in geostationary orbits around the equator and are in constant view of large portions of the Earth (excluding the artic/antarctic areas - the LEO satellites can still see those and hear the Beacon with GPS location). The accuracy of GPS location isn't a good as a handheld GPS because some of the data is truncated (as I understand it), but it still is within about 350-600 feet.
The PLB with a preloaded GPS coordinate will provide the closest thing to a 10 second signal, but the ACR PLB will only hold that location in memory for 4 hours.
Looking at Doug's PLB test results, it looks like a PLB with a good view of the sky will take 1.5-2 minutes to be able to send the GPS location.
One thing that is interesting is that in order to save power (GPS's take relatively lots of power), once a good GPS location is obtained the ACR PLB shuts down the GPS and then it turns the GPS back on to look for a new location every 20 minutes. That seems like a reasonable comprimize to keep the 240 MHz beacon functioning as long as possible (24 hours minimum for the ACR PLB).
I'm such a geak!!