During my adult lifetime, there has been some improvement in how potential jurors are treated by court systems. When I was first summoned for jury duty by Cook County in the 1980s, potential jurors were treated like cannon fodder. They're basically free to the court system, so their time was wasted by stupid inefficiencies. By a decade later in Cook County, potential jurors seemed to be treated better. In Los Angeles County, it's still clear that jurors come last in priority in the court system.
Here's a 1992 letter-to-the-editor in the NYT by a citizen named Robert E. Lupinskie suggesting videotaping trials without juries, then showing the juries the edited videotapes without all the disallowed testimony, sidebars, adjournments, and other time-wasting. Serving on a jury takes up a lot of days because the judge and lawyers work on other cases in the morning and afternoon when the trial is not in session. For example, on the trial I served on, we would normally be told to show up at 10 in the morning, but often the judge was conducted a very serious looking hearing with a defendant in a different case shackled to the defense table, so we'd go sit in the jury room until 10:30 or 11:00. We'd take 90 minutes for lunch and be out by 4:00. We didn't work very hard, but we were there a long time. Testimony in that trial lasted something like 9 business days, but we could have watched all the proceedings on edited videotaped in 3 or 4 days, working 7.5 hour days.
I can't think of any obvious reason this would be worse than the traditional system and several reasons why it would be better.