I'm not fucking around here: the beer community needs to put to bed the idea of "sessionable IPA." The concept makes no sense. In the most generic definitions, "sessionable" refers to a beer under about 4.0% abv with well-balanced malt and hops profiles such that you can have several throughout a drinking session without getting shitfaced.
When brewed to style, IPA's are generally around 6-7% abv and are hopped the fuck out*. That description could almost be paraphrased as "non-sessionable beer." If you have three or four IPA's and aren't drunk or pretty close to it, you've got a very high functioning liver. If you have three or four IPA's and can still taste anything after all those hops, you've got a stronger tongue than I or you're drinking a lightly hopped beer that probably shouldn't have "IPA" on the label. Standard IPA's are not sessionable, no matter what anybody writes in a beer review or on-the-bottle description.
But say you're a brewer and you really want to concoct that elusive "sessionable IPA." What do you do? Reduce the alcohol content and tone down the hops, of course. What do you get when you do that? A FUCKING PALE ALE. And there's nothing wrong with that. For the love of god, though, just call it a pale ale! If you get the alcohol content low enough, pat yourself on the back, call it a sessionable pale ale and go enjoy a whole six-pack of 'em. You've earned it.
For everyone else, say it with me: IPAs are NOT SESSIONABLE. Never will be.
* That's a technical term for a beer with high bitterness, 50-70 IBU, and lots of aromatic hop characteristics.