Yes, so for example if you were searching for "elephant" and matched "ele", then you could only advance by 2 since the 2nd "e" might be beginning of "elephant",

Yes, so for example if you were searching for "elephant" and matched "ele", then you could only advance by 2 since the 2nd "e" might be beginning of "elephant", but if you matched "elep" than you could advance by 4 since "ep" is NOT a prefix of "elephant". But still, it all comes down to how far can you advance at any given match failure position.