To borrow a line from a book — one of those things I read before TV swallowed all my spare time — for critics, these are truly the best and worst of times.

As is so often the case with critics, let’s start by accentuating the negative.

Mass-circulation newspapers are experiencing hard financial times, prompting many to reduce arts coverage. The result is an unsettling debate about eliminating local movie and television critics, as publishers allocate limited resources elsewhere.

And TV critics find themselves evaluating shows most of their readers haven’t seen, thanks to increasingly fragmented viewing. Moreover, the explosion of channels and time-shifting technology has made it easy for the audience to sample shows and bail out at the first tinge of boredom — without the need to consult reviews.

Small wonder that former NBC West Coast president Don Ohlmeyer once dismissed TV critics as possessing the collective utility of “teats on a bull” — which is to say, having virtually no use at all.

On a personal level, the logistics are formidable, in part because I endeavor to watch TV the way “normal” people do — that is, on the couch, usually alone and in a state of undress. Because TV viewing is generally a solitary pursuit, this means skipping splashy premieres of programs I’m reviewing, lest an audience influence my reaction. Marathon viewing sessions are also a bad idea, so it’s advisable to break up the process to maintain fresh eyes, along with one’s sanity.

Being a critic in Los Angeles is unique in that you write for two constituencies — potential viewers, along with the people who make the shows — and risk bumping into the latter after trashing their work. As long as you’re fair, this shouldn’t be a problem, but attending a recent pre-Emmy party, I confess to having felt like an open-field running back — dodging this way and that to avoid those who might resent someone who had called their baby ugly.

The license to publicly render such verdicts brings to mind “Manhattan,” when Woody Allen is accused of thinking of himself as God. “I gotta model myself after someone,” he responds.

While TV criticism entails relatively few perks, the near-divine right to the last word remains one of them.

Because television criticism seems especially disposable, some TV critics espy those in other disciplines with a sense of envy: People are more apt to want to make informed decisions before plunking down $250 for theater seats, or movie tickets, popcorn and a baby sitter.

And then there’s the Internet, which allows viewers to supplant the critic’s traditional role through blogging and by establishing online communities to discuss programs. It also hastens feedback, at times releasing torrents of unfiltered vitriol — almost invariably, if something you’ve written gets posted on the Drudge Report.

So to recap: There are far more options, with fewer people seeing any one of them, while critics’ very existence is under siege.

But that’s only half the story.

Although people can peruse shows at will, the glut of original programming fosters a hunger among savvier viewers for guidance to sort through the fog. Moreover, prestige-conscious networks such as HBO and Showtime are extremely sensitive to criticism — cultivating raves for little-seen series such as “The Wire” to entice subscribers, part of a pay-to-view dynamic (along with DVD sales and downloads) that somewhat levels the critical playing field vis-a-vis theater and film.

Websites that aggregate reviews, such as RottenTomatoes or Metacritic, also disseminate critical opinions to wider audiences, which explains those emails from residents of landlocked states who otherwise would never read Variety.

These avenues facilitate a dialogue between critics and readers that — even when laced with scorn — can be helpful in refining what we do, as opposed to just hurling thunderbolts from above.

The disappearance of lulls in the TV calendar has undoubtedly made the job more taxing, but the heightened ambition and quality of the best programs mostly compensates for the additional tonnage.

Finally, it’s time to bury some erroneous folklore about critics.

1) People think we enjoy bad reviews more. Negative pieces can be a lot of fun to write, but nobody likes sitting through dreck to get there, so you always hope whatever you’re seeing is good.

2) Variety critics are especially vulnerable to industry pressure. We hear this occasionally, and it’s bull. Most people understand that critics bite the hands that feed their publications. Tough but fair is the goal, as it should be for any critic.

3) All critics are frustrated (fill in the blank). Sorry to disillusion you, but I have zero desire to write TV shows or movies — a character failing that I attribute to being allergic to large quantities of money.