WITNESSES RPRTD ACFT WAS HI DRG APCH & LNDD NOSEWHEEL 1ST ABT 1600' BYD THRESHOLD, THEN BCM AIRBORNE & BOUNCED 2 TIMES. PLT STATED THAT BFR TCHDWN, HE STARTED TO 'SPOOL UP' ENGS, BUT NOTED LACK OF RESPONSE, THEN RETARDED THROTTLES & LNDD. HE SAID HE APPLIED BRAKES & SELECTED 'FULL REVERSE' & NOTED NO RESPONSE. RPRTDLY, NOSEWHEEL 'SKIPPED INTO AIR' WHILE ACFT STILL HAD FLYING SPEED. WITH INSUFFICIENT RWY RMNG TO STOP, HE ELECTED TO STOW REVERSERS & BGN GO-ARND. HE NOTED NO RESPONSE FM ENGS, THO ACFT HAD BCM AIRBORNE. ACFT THEN SETTLED BYD DEP END OF RWY & CRASHED ON ROUGH TRRN. EXAM REVEALED ENGS HAD INGESTED TWIGS, GRASS & DIRT. REVERSE LOAD LIMITERS (L/L) ON BOTH ENGS WERE FND IN TRIPPED PSN. FLT MAN STATED THAT TO AVOID ACTUATION OF L/L, DO NOT ADVANCE PRIMARY THROTTLE AFTER RTRNG REVERSE THRUST LEVER TO STOW UNTIL UNLOCK LIGHT IS OUT; MAINT REQUIRED TO RESET ACTUATED L/L. L/L WAS INCORPORATED ON THRUST REVERSER TO REDUCE ENG PWR TO IDLE, IF INADVERTENTLY DEPLOYED IN FLT. DRG POST-ACDNT CHK, BOTH ENGS WERE OPERD TO 85% AFTER L/L RESET.