I believe Sylvan uses MyLaps active chips. This means that there is a battery in the chip that emanates a signal to the RFID reader. This is called active RFID. Most timing companies use passive RFID, which means that the RFID reader looks for chips to come into the electrical field and register. The active system is very near 100% capture of data. I would be surprised if they miss one time stamp in all of the segments of a triathlon. Where the active and passive systems really differentiate is the swim data capture. I believe all passive timing systems have some degree of difficulty making that swim read, due to water on the chip. With active systems, the problem of water on the chip is eliminated, as the battery is emanating a signal.
Passive systems generally read well over 99%, often above 99.8%.
For this and many other reasons, Sportstat is the top timing company in the world.
Just another reason to have multiple means of verification and not rely on a single technology.