However, the fact that cans, unlike bottles, are opaque is a significant drawback. With a bottle, you can check that the yeast has settled to the bottom, and then pour it carefully to ensure it doesn’t get in the glass and you end up with a clear drink. However, with a can, you simply can’t do that, so you have to trust to time and as to whether the yeast has settled, and depend on very precise timing to minimise the amount that ends up in the glass. For this reason, regardless of the inherent merits of the container, I’d say cans are not an appropriate medium for container-conditioned packaged beers.
Of course, you may not be much concerned with clarity in the first place, and Justin Hawke of Moor is well known as holding the view that too much importance is given to clarity in beer in the first place. Some, of course, might argue that’s just a case of claiming a defect as a feature, and, overall, cloudy or hazy beer is something the vast majority of beer drinkers actively avoid. Especially with a can, there’s a reasonable expectation that the contents will be crystal clear. Maybe a big warning notice is needed.
There’s also a possible question mark as to whether there actually is a genuine secondary fermentation in the can. Just having a bit of yeast in suspension doesn’t ensure that. Some US imported cans, such as the Sixpoint Bengali sold in Wetherspoons, are cloudy, but they don’t claim to be can-conditioned. And, realistically, is the CAMRA imprimatur going to make any difference to whether or not people drink it?
I’ve always maintained that it was an error of judgment for CAMRA to take the view that the relationship between bottle- and brewery-conditioned packaged beers was the equivalent of that between cask- and brewery-conditioned draught. For very good reasons, bottle-conditioning in the UK had largely died out decades earlier, and wasn’t in any sense a live tradition worthy of preservation, as cask was. In the 1970s, with the off-trade only accounting for a small proportion of overall beer sales, it didn’t matter all that much, but the effect today is to dismiss as unworthy of consideration many beers of high quality, while encouraging small brewers to produce inconsistent and hard-to-handle bottle-conditioned beers that are guaranteed to deter the ordinary drinker.
Yes, in these terms, can-conditioned beers do quality as “real”, but it’s very hard to see the early members of CAMRA from the 1970s being remotely comfortable that the organisation has ended up giving the seal of approval to kegs and cans. To quote George Orwell from Animal Farm, “The creatures outside looked from pig to man, and from man to pig, and from pig to man again; but already it was impossible to say which was which.”