Yes, there is some black magic in the statement itself.
You could call RFC_PING (physical connection test in SRFC) before you call RFCPING (application authentication test in SYST), but you don't have to. The CALL FUNCTION func DESTINATION statement has built in exceptions which it throws back to the calling program that either the server could not be reached or it was reached but failed to respond. You can catch those exceptions in addition to any exporting parameters from the FM itself. See transaction ABAPDOCU for the DESTINATION statement.
Cheers,
Julius