Logging spread at entry changed which pairs I keep trading

[FXS London Scalper]

For years I logged only entry, stop, target and result. Three months ago I added one more field: spread at the moment of entry, in points. It took about two seconds per trade. It ended up changing my pair list.

After roughly 600 trades:

• EURUSD: average entry spread 0.2 pips. Fine.
• GBPUSD: 0.6 pips on average, but 1.4 pips on the trades I took in the first five minutes of London. Those trades were clearly negative after costs.
• EURGBP: 0.7 pips on average for a pair with small ranges. My gross edge existed, net edge almost zero.
• XAUUSD: wide variance. On calm days fine, on data days the spread at entry was often 3 to 4 times normal.

Result: I dropped EURGBP completely, stopped trading GBPUSD in the first five minutes of London, and added a hard rule to skip gold when the spread is more than double the hourly average.

The P&L didn't jump overnight, but the losing clusters got smaller.

If you don't log spread at entry yet, it's probably the cheapest improvement you can make to your journal. Has anyone done the same and found a pair that looked good on the chart but bad on costs?