Supporting craft breweries

The terms have nothing to do with anything much. It's the Spinal Tap volume knob of beer nomenclature: three is a bigger number than two, and four is bigger than three. That's all.

The tradition you're referencing there is American and no older than the 1980s. In 19th and 20th century British brewing, where IPA came from, it was often among the weakest beers in the portfolio. Plenty of breweries didn't make any distinction between what was called a Pale Ale and what was called an IPA: the terms were just as makey-uppy then as they are now. It was only when the Americans arrived in that they decided there ought to be a system, so they invented one. Nothing traditional about it.

The double, triple, quadruple IPA thing doesn't refer to hop quantities. Brewers aren't working to a manual or rulebook that they can see but we can't. They're just making things up as they go along.

IPA was never shipped to India. When the colonists returned, and wanted to keep drinking the beer they used to get in India, breweries like Bass and Allsopp began making a product called "Pale Ale As Prepared For India" ie a local beer that's like what gets shipped to India. This was then abbreviated to India Pale Ale.

There's no direct evidence that the pale ale shipped to India was brewed extra strong. Advice for brewers making beer for export by ship were told, most importantly, to attenuate it out completely, so warm weather wouldn't kick off new fermentation and explode the casks in the hold. This unusual dryness is probably what gave the beer its distinctive character and made it popular with the colonists. There is advice for brewers making porter for the Caribbean trade that they should add extra hops, and so it's likely that beer going eastwards got the same treatment, but there's no direct evidence that pale ale being shipped to India got extra hops.

The story that IPA was an extra strong (and extra hoppy) to survive the journey to India was made up by American homebrewers in the 1970s. Historians like Ron Pattinson and Martyn Cornell have looked at the actual sources and debunked it thoroughly years ago.

Paragraph two of his Wikipedia page, citing his obituary in The New York Times, says "He is credited with helping to start a renaissance of interest in beer and breweries worldwide in the 1970s, particularly in the United States". He was extremely influential on the early American microbrewing scene. Your point remains thoroughly unproven.

I think maybe you have misunderstood what I was trying to say. To recap: IPA as the central feature of "craft beer" (for want of a better term) as we know it today is an American thing. English IPA was all but dead by the end of the 20th century, with just a handful of hangers-on. Then came Sierra Nevada and the other west-coast brewers: looking to English IPA for inspiration but using fresh local hops to make American IPA its own thing. The American microbrewing movement hadn't really had a style of its own -- the Samuel Adams flagship was a Vienna lager; Pete's Wicked was a brown ale -- but when the hop craze properly took off, American IPA was it, thanks to the likes of Stone and Ballast Point going all-in on big hops and big alcohol with a big attitude. By the mid-2000s, the American IPA concept had been exported: Jaipur and its offspring Punk in the UK; Galway Hooker the first baby step here on the route to what would later bring us Flora & Fauna, Of Foam & Fury and all the other big hop-blast American-style IPAs that we now take for granted. Craft-brewed IPA is an American concept, wherever the beer happens to be brewed and consumed.

With the concept, came the story. American brewers trying to sell the first modern American IPAs needed to tell people what it was. They knew that hops were central to the beer's character; they knew that they were brewing it stronger than English pale ale; and they knew that export to India featured in its history. These three facts were embroidered together into the (not unreasonable) idea that IPA was an extra-strong, extra-hoppy version of pale ale, made for export to India. They invented a sliding scale of strengths with pale ale at the low end and IPA at the high end, because that's the way they ran their breweries' ranges. Nobody at that point knew any better, so that became the "official" origin story. But that doesn't mean it's true. We now know it isn't: for 19th century British breweries, pale ale and IPA were largely synonymous terms, not two different products in a range.

English breweries didn't do marketing like this. They didn't need to. Customers went to the pub owned by their local brewery and drank what was there. They didn't need a whole origin story. The origin story is a feature of 1980s American marketing, and where it exists on this side of the Atlantic, we got it from there when we adopted their way of doing beer.

In Europe, brewing had to stop for the summer because it was too warm. There was NO chance that a 19th century brewer could make acceptable beer in the Indian climate. It had to be shipped.