ECHO progressive handicap

ECHO (Echo Handicapping System): the Irish national progressive performance handicap, used for cruiser racing across Ireland. Each boat’s handicap is blended with its Performance Index (PI) after every race. Default α = 0.25 for club racing; 0.50 for regattas. Reference: Irish Sailing 2022 ECHO Guide for Clubs.

Examples

#	Scenario
1	ECHO — Irish Sailing 2022 ECHO Guide for Clubs, page 2 worked example
2	ECHO — non-finisher (DNF) carries handicap unchanged
3	ECHO — competitor without echoStartingTcf is rejected from the fleet
4	ECHO — multi-race handicap propagation across two races
5	ECHO — fewer than three finishers suppresses the rating update
6	ECHO — α = 0.50 (50/50 split, regatta preset)