What made Abbott work really well is there are times where he ISN’T the straight man and is actively doing stuff to get Costello in trouble. I believe in Buck Privates he imitates Lou’s voice to get a Drill Instructor angry at Lou.
Does anyone else find it sad that these people were making more in the 1930s-40s than I have ever made? That’s not even accounting for inflation. The wife and I together don’t make that much now, and the wife has a really good paying job.
Was he really doing the impersonation, or was he lip- synching to Lou?
I don’t remember the Buck Privates scene, but I found it interesting that in the early days of performing on radio, they found that the audience had trouble keeping track of who was speaking, because their voices were so similar. That’s why Costello adopted the artificial high-pitched childish voice that he used thereafter.
I think it’s fair to call the team mediocre. They certainly performed some of the greatest comedy routines in film history; but much of their work is so-so to actively bad.
They were popular, but that has nothing to do with how good they were.
After WW2 most of the classic comedy teams were gone. Besides (ugh) Lewis & Martin, who were the big teams post war?
eta: am I going to see a big outpouring of love for Lewis & Martin like I unleashed with A&C? 
“Who’s on First?” for one. It was usually Costello getting annoyed with Abbott who played the conman more often than the straight man.
Smothers Brothers. Never succeeded in a movie, but they were huge in the 1960s and kept up a career until the end.
Mom always did like them better.
George Burns and Gracie Allen.
Ruth Buzzi and Arte Johnson on Laugh-In.
Shields and Yarnell.
From the Wiki page on Double act
In the United States and Canada, the tradition was more popular in the earlier part of the 20th century with vaudeville-derived acts such as Laurel and Hardy, Abbott and Costello, Burns and Allen, Wheeler & Woolsey, and Lyons and Yosco and continuing into the television age with Martin and Lewis, Kenan & Kel, Bob and Ray, the Smothers Brothers, Wayne and Shuster, Allen and Rossi, Jack Burns and Avery Schreiber, Rowan and Martin, Mike Nichols and Elaine May, the Wayans Brothers, Stewie Griffin and Brian Griffin from Family Guy and Shawn and Gus in Psych. The series I Love Lucy was known for its double acts, and Lucille Ball served as foil to both her husband Desi Arnaz and to Vivian Vance. Vance could also serve as foil to William Frawley when the situation required. Vance and Ball would again serve as a double act in their next series The Lucy Show.
More recently, the model has been largely supplanted by that of the “buddy movie” genre, which has introduced several notable comedy partnerships not formally billed as a single “act” in the traditional manner. The earliest example of such a team may have been Bob Hope and Bing Crosby; later examples include Gene Wilder and Richard Pryor, Burt Reynolds and Dom DeLuise, Dan Aykroyd and John Belushi, Corey Haim and Corey Feldman, David Spade and Chris Farley and child stars Drake Bell and Josh Peck.
Based on the gag-man/straight-man concept, “Stoner” duos like Cheech & Chong, Jay & Silent Bob, and Harold & Kumar have also proven quite popular with audiences.
The double act format can also be used in presenting noncomedic information in an entertaining manner, such as Savage/Hyneman pair of the Discovery Channel’s MythBusters (which Savage stated was unintentional when they began the series but naturally grew into a double act as the result of their own conflicting personalities)
[Edited for clarity. Broke up a wall-of-text into more readable paragraphs.—mbh]
Didn’t Britain have some? (Morecambe and Wise, Peter Cook and Dudley Moore, and of course Monty Python) Or is that too late?
Bob Hope and Bing Crosby? Jerry Stiller and Anne Meara? Mike Nichols and Elaine May?
You’d probably want The Goons (Spike Milligan, Peter Sellers and Harry Secombe) for a solid post-WWII UK comedy team. Fourth member Michael Bentine departed early for other work but apparently on good terms.
The best way to judge the work of Abbott and Costello is to watch a lot of their movies. You can find 73 of them at https://www.youtube.com/playlist?list=PLBFa2yUBFRr74T53yOb2zHkNIY4-OrHjs and watch them for free. It says that there is another eight of them not available, presumably because the copyright holders didn’t want to allow people to watch them for free. I certainly would be reluctant to offer my opinion of the body of their work having seen just a few of their films (and, more precisely, just a few of their sketches).
Among the most prolific in film, Franco and Ciccio - Wikipedia. “Many Americans consider them to be the least funny comedians they’ve ever seen” (The Psychotronic Video Guide, St. Martin’s Press, 1996, pg. 16).
There have been lots of mediocre comedy duos. Are you aware that Lorne Michaels of SNL was once part of a comedy duo with Hart Pomerantz? You can see and hear some of their work in https://www.youtube.com/watch?v=4gXQAt8VBbs and https://www.youtube.com/watch?v=NIl8e_unnuQ .
And the oddest pairing of all: Jack Burns and George Carlin. Burns got top billing.
That was before Burns teamed up with Avery Schreiber and made lots of appearances on Ed Sullivan and got their own variety show.
Sullivan loved comedy teams. The Canadian duo of Wayne and Schuster were on the show 58 times. Stiller and Meara had 29 appearances. The vaudeville team of Smith and Dale lived long enough to be on 20 times.
Comedy duos still exist. The Sklar Brothers, the Lucas Brothers, and Cory and Chad, the Smash Brothers, are all sets of identical twins on the road today.
Mitchell and Webb and The Mighty Boosh are two modern duals. Fry and Laurie is one I really wish would reunit.