How MACD-V differs from standard MACD
Standard MACD is an absolute price difference. A one dollar EMA gap has a different meaning for a 20 dollar stock and a 500 dollar stock. MACD-V scales that difference by ATR, which gives the result a volatility reference.
The normalized value can be compared more directly across markets, but the denominator creates a new dependency. A jump in ATR can reduce MACD-V even if the EMA gap does not change. That behavior should be part of the test, not treated as an error.