The Russian was a key player in the third season’s best episode, “The Pine Barrens,” in which Christopher (Michael Imperioli) and Paulie (Tony Sirico) allow a murderous Russian mafioso, whom they tried and failed to kill, to escape into the icy back woods of South Jersey. Chris and Paulie spend the episode tramping through snow and freezing their butts off, trying in vain to find the Russian. They succeed only in getting themselves lost. The Russian hasn’t been heard from since. Among fans, he has loomed like a bogeyman–but he shouldn’t. He’s gone. He’s not coming back.

One of the many marvelous things about “The Sopranos” is the way mistakes don’t always come back to haunt its characters–kind of like real life. Sometimes, we just we get away with things. Sometimes, our problems conveniently disappear. Other times, they remain painfully unresolved. No neat bow, no happy ending. In the first three seasons of “The Sopranos,” such loose ends were so rare that when they happened, it was obvious that series creator David Chase and his staff of writers were making conscious choices to leave them that way. The biggest problem with the current season of “The Sopranos” is that it’s happening way too much now. Loose ends are everywhere in season four, and the more it happens, the less it feels like Chase and Co. are making smart choices. It just feels sloppy.

What happened to Meadow Soprano? In this season’s first two episodes, Tony’s daughter (Jamie-Lynn Sigler) was a depressive wreck, in hysterics over her murdered boyfriend, Jackie Jr., and plotting to drop out of Columbia for a year of traveling in Europe. Tony said no, he and Meadow had a big fight, and then Meadow vanished from the show. When last we saw her, during a mid-season episode, she was back at Columbia and happy as a clam. Huh?

Then there’s Adrianna, Christopher’s girlfriend (Drea de Matteo), who’s currently tangled up with FBI. At least, I think she is–because the plotline, which got rolling in the season’s second episode, has barely moved since. The Adrianna/FBI subplot will surely go somewhere–or perhaps cleverly nowhere; Chase’s writers are geniuses at defusing major crises in satisfying ways–but the story has gone about 10 episodes now without much development. A few weeks after infamously projectile vomiting atop an FBI interrogation room table, Adrianna was back out shopping with Carmela and the other mafia gals. Like Meadow, happy as a clam. Huh? Wasn’t A.J. having major behavioral problems last year? He’s fine now. Wasn’t Silvio briefly undermining Tony, contradicting the boss’s direct orders on a construction site deal? That’s over now.

Throughout this fourth season (which wraps up a week from Sunday) viewers and critics alike have complained that “The Sopranos” has lost a step, that this batch of episodes has been the show’s worst to date. This is indisputably true. “The Sopranos” has lost a step. This season has been weaker than the first three. Of course, from the start, viewers and critics have warned each other that the show would surely slip at some point, that there’s no way it could be this good forever. So why are we all so surprised–or, judging by the friends I’ve spoken to about this, downright annoyed–that our prophecy has come true? Folks, cut “The Sopranos” some slack. It’s still pretty great. In fact, despite quite a few stumbles this season, it’s still the best show on television.

No story line better illustrates what’s wrong–and, paradoxically, what’s still very, very right–with this season of “The Sopranos” than the demise of Ralph Cifaretto, Tony’s reckless, slimy captain, played marvelously by Joe Pantoliano. In Ralph’s last two hours on the series, consider all the things that happened to him: (1) he is unmasked as a sexual masochist by an ex-girlfriend and, in all likelihood, a deeply closeted gay man, then (2) his young son is nearly killed in a backyard accident, then (3) his prized racehorse dies in a fire, then (4) he is murdered at the hands of Tony, who suspects he set the stable fire. All in two hours. Talk about whiplash! This is just too much, too fast. And worse, Nos. 1 and 2 have little or nothing to do with Nos. 3 and 4. The writers raised the possibility–the rather interesting and unexpected possibility–of Ralph being gay, then got bored and dropped it. Next thing you know, he’s dead. The show, overall, has become too random.

But boy, has it been fun to watch. Ralph’s downward spiral was a ridiculous ride, but each stop along the way yielded some awfully unforgettable moments. In the entire history of “The Sopranos,” I have never laughed harder than I did during the sex scene between Ralph and Janice, Tony’s conniving little sister, played by Aida Turturro. Janice, as per her lover’s instructions, is sodomizing Ralph with a vibrator and calling him degrading names when his cellphone rings-and the phone chimes out the “Rocky” theme. (Far from being anti-gay, this is actually the opposite: it’s anti-homophobic. The writers are lampooning the silly lengths to which a macho gangster will go to repress his sexuality.) A few episodes later, after Tony has learned about Ralph’s curious sexual habits, he asks Silvio if he thinks Ralph has any issues with women. Silvio pauses for a moment, then says, without any irony, “Well, he did kill one once.” On the other end of the spectrum, there’s the scene in which Tony murders Ralph–a heart-stopping brawl in Ralph’s kitchen. Most of its power comes from its realism, and most of its realism comes the fact that it’s so clumsy. Real fights aren’t elegant. They’re desperate and vicious. Tony and Ralph’s was among the most convincing I’ve ever seen. And like so many moments on “The Sopranos,” I never saw it coming.

“The Sopranos” right now reminds me of the final years of the Beatles, around the time of “Abbey Road” and “Let it Be,” when John and Paul and George were hardly speaking to each other. Their music in those days was electrifying, but the albums didn’t feel like cohesive creations. They were just one great moment after another, with some lulls and pointless digressions in between. They were incomplete, often frustrating. But heck, it was still the Beatles. Television’s best show isn’t as perfect as it used to be. But heck, it’s still “The Sopranos.”