Sour IPAs? Gimmicky or legitimate style?

Beer styles are not set in stone and neither is there any official body to define them.
They arose from names used by brewers,often indiscriminately and interchangeably.
IPA has existed in so many guises that it is impossible to pin down just what it is.Just one sort of Pale Ale (and these need not be pale as the name is derived from the use of Pale Malt)
The Romans , Lord Nelson and the captain of the Titanic all knew what a ship was.They were all right but different.
One of the best selling ales in the UK is Greene King IPA. It is 3.6 %ABV and about 30 IBU.Some people with superficial beer knowledge say it is not an IPA. But it is ,but a 20th century example.

 

What makes them an IPA though? What does "sour fermented" mean?

 

They were both hoppy and id say tart at the same time. The one beer used citra powder and the other monteuka. Sour fermented as in inoculated airborne with whatever "yeasts" are floating around their area.

 

Not a fan, I do love a good dry hopped sour (more farmhouse style) but have not enjoyed any beer labelled a sour IPA. I find them terribly unbalanced. Slightly tart would be ok.

 

*Ding Ding Ding*

As a home brewer this ^^^^ was the first thing I thought.

Its either a weird mashup of a beer or a way to save a batch that's been soured accidentally. Not saying there aren't tasty examples, but I think we are much closer to it being a 'passing fad' than being a 'legitimate style.'