So much so that from some production areas it can be worse from a ghg perspective than coal.

For a few decades. Methane decays in the atmosphere, while CO2 sticks around for however many centuries until it's physically sequestered.

Methane decays into.... Co2 and water vapour. Both have further green house impacts.

And yet, when there's a big leak, flaring it is the way to go.

And if it's an illegal leak, maybe it needs some help to flare.

Yes, I agree - I'd rather they flare methane and not just leak it. But I wanted to ensure that people didn't think methane just harmlessly decays away. Water vapour at high altitudes causes green house warming, as does the co2 - so while it isn't as bad once decayed, it isn't harmless.

Over 20 years it traps 84x times as much heat and 28x over 100 years. I believe most EPA calculations use the 100 year timescale. So if there's 4% leakage (there are some fields that exceed this) its worse than coal on 100 year timescale.

Its arguable what the correct timescale to consider it is. Personally I think 100 years is too long given methane's potential feedback effects. IE, warming causes methane to be released from Arctic tundra melt causing more warming, etc.

And there's also the issue that the higher the concentration of methane in the atmosphere the longer it takes to decay.