Why it matters
Knowing the spread regime keeps you from trading a scalping strategy in a non-scalping market.
Trading use: the point is not vocabulary. The point is prediction: what changes when this shows up?
Common trap
Using a fixed stop/target without considering that costs doubled.
Example
EURUSD spreads are tight during London, but widen noticeably at NY roll.
Operational cue: if you can’t point to it on the chart, in the DOM, or in your broker logs, treat it as a story and trade smaller.
Notes
Quick rule
- If you see this repeatedly, you are in a different regime than your model assumes.
- Regime change usually means position size change.
- When in doubt: trade smaller, or don’t trade.