I tested the candle size filter on EURUSD M5 during London and it cut more noise than the RSI one. RSI(14) divergence shows up all through a steady trend on that timeframe, so alone it let in plenty of tops that were only pauses.
I also added a minimum gap of 8 bars between peaks. Two highs three candles apart are usually one consolidation rather than two attempts, and those failed most often in my sample.

- img_13735_r1.png (65.95 KiB) Viewed 9 times
The illustration shows a setup passing everything: peaks at 1.1684 and 1.1685 eleven bars apart, RSI 86 then 73, and bodies into the second high about a third the size. Entry is the close at 1.1670 under the 1.1672 neckline, stop at 1.1688.
That stop is the weak spot. It is 18 pips when the average M5 bar there is about 4, so on some trades I now wait for a neckline retest and put the stop above the retest high.
The trade count dropped from about 140 setups over six months to under 50. I would not read much into expectancy until it has a few more months behind it.
Has anyone tried the same filter on double bottoms in New York? I suspect the candle size part behaves differently there.