Editor’s Note: With Tim Carman away on vacation, Young & Hungry invited Greg Engert, the beer director for the Neighborhood Restaurant Group, which includes ChurchKey and Birch & Barley, to blog in his absence.

As I was tap-tap-tapping out some (maddeningly terse) tweets over the past week, I was amused—then alarmed—to realize just how much I draw attention to the “craft” aspect of the multitudinous new drafts we tap with tenacity. Other adjectives I found myself over-employing in the tweet-osphere included “authentic,” “real,” “honest,” “true,” and “traditional” (apparently, in my quest for concision, terms that I tend to use in the longer format of conversation, like “uncompromising” and “microbrewing,” just seem to teem with too much “character” for Twitter…). At first I was embarrassed at my apparently limited verbal arsenal, but then I started to see just how heavily I—and others—tend to lean on these presumably agreed-upon terms in an effort to succinctly champion the merits of these “beers-not-made-by-mega-industrial-brewers.”

What began as an exercise to broaden my Twitter lexicon turned into a rumination upon the merits of those crutch words. Feeling as if—through mere repetition—terms like “craft brewing” had become bereft of meaning, I started to join the fracas over just what “craft beer” and “craft brewing” serve to signify, or once did.

The Brewers Association, a trade organization that “promotes and protects small and independent American brewers,” has a working definition for craft breweries that stems largely from its political work on behalf of said breweries. One facet of this definition includes a reference to the size of small and independent breweries as viewed though the lens of beer production: a craft brewer has an annual production of beer less than 2 million barrels.

Their definition is much more multi-faceted than mere production numbers, but I seize upon this particular aspect because it will most definitely soon change (whereas the other portions of the definition seem static).

The Brewers Association has been working with Congress to achieve a cut in the excise tax that craft brewers—those producing less than 2 million barrels per year—have been paying at the current level since 1976. At that time, the Brewers Association of America, which merged in 2005 with the Association of Brewers to form the Brewers Association we know today, secured a tax differential on the first 60,000 barrels produced by a brewery that made no more than 2 million barrels of beer per year. What must have seemed an impossible mark of production for small brewers to overcome almost 35 years ago, will certainly be exceeded by the Boston Beer Company (the brewers of Sam Adams) by 2012 at the latest.

And this remarkable growth by one of America’s craft brewing pioneers seems to be affecting an overhaul in the conception of craft beer in America, at least on the political level. U.S. Sen. John Kerry of Massachusetts recently introduced a bill that aims to lower the excise tax from the levels imposed in 1976, but are also seeking to extend this cut to brewers who produce no more than 6 million barrels.

I do not want to argue the merits or shortcomings of the BA’s definition of craft brewing, nor of the countless definitions proffered by beer writers, bloggers and pundits. What is far more interesting to me is the incessantly evolving nature of “craft” brewing in America, a constant evolution that continues to defy and elude categorical definitions. As breweries we associate with craft beer become more and more successful, they expand and increase production. In this way they are not all that different from any other American business on the upswing, including the industrial “macrobrewers” to which craft brewers seem diametrically opposed (what certainly remains different between the “macro” and “micro” is the flavor and overall quality of the product produced).

It seems that a week does not go by without a craft brewery announcing plans to expand, to merge with another craft brewery, to purchase another craft brewery, or even to build another branch of a craft brewery abroad. Coming to terms with just what this means for craft brewing is a formidable task, but what is for certain is that the state of craft brewing in America is in constant and exciting flux.

The debates that continue to arise as to what craft brewing is are inevitable and often interesting. What I find more interesting is the need for craft beer drinkers, myself included, to pin this down, to specifically signify when identifying something as craft-brewed. And these debates always seem to intensify in the face of further complexity, as if craft beer drinkers need to maintain a sort of ownership and authority over a product that is becoming harder and harder to identify by definition. Perhaps even more importantly, the industry is becoming more complex and more difficult to understand and define just as it is also becoming more popular and—dare I say it?—mainstream.

There is a sort of identity crisis in the expanding and increasingly competitive world of craft brewing. Business is good for craft brewers and they are increasingly reminded that they are in fact businesses, businesses that have to worry about profitability and the economics of scale. The simpler notion of craft brewing as the endeavor of small, local artisans is becoming more difficult to maintain as the line between macro and micro will only continue to blur (but only blur in the sense of statistical data that can seem to help us when it comes to definition). Definitions are attempts to reach seemingly objective conclusions and numerical data is best suited for this. However, if the craft brewery “definition” expands to include breweries producing up to 6 million barrels annually, Pabst Blue Ribbon would technically be a craft beer with regard to that facet of the definition. And this alerts us to that which data and definition deny: the import of flavor, quality-driven production, and—by extension—subjectivity in this entire debate. It is the insistent deliciousness and quality of the beer as determined by the consumer that distinguishes “craft” beer from the “megabrewed.”

There are larger craft brewers that make delicious beers of terrific quality and there are tiny producers that brew beers with little-to-no flavor distinction. The debate cannot be about size, but more about the ability for brewers of all shapes and sizes to produce beers so flavorful one cannot help but drink them. If craft beer is simply beer that is continually interesting and flavorful, then it becomes the arena of individual subjectivity. I feel like this kind of definition has the tendency to make the old school beer intelligentsia uneasy because it undermines their grasp on and authority over an industry that was once much simpler (and that they once had had all to themselves). I have been noticing a sort of anxiety lately among the beer geeks who loved flavorful beers before they were hip and I think it has much to do with the growth of craft beer in general.

As more and more flavorful beers spring up from growing craft breweries, more and more people begin to enjoy them. The prevailing—more objectively based—definitions of craft brewing no longer hold and what is left is a sort of subjective idea of craft brewing that foregrounds quality and flavor over production numbers or ingredients employed. The source of this anxiety is therefore two-fold: older, narrower presumptions about craft brewing are losing traction, just as the number of people who can call themselves craft beer drinkers is rapidly expanding. In the end, debates about what craft beer is may in actuality be a burgeoning debate about who craft beer may be.