A lot of questions is an understatement. On average there was one question every 20 minutes or so during the time when there was a witness in the box.
Bear in mind that any juror may ask for a question to be asked. It's extremely unlikely that of the >150 questions that were asked, every juror asked roughly the same number.
Asking such a huge number of questions, probably smashing the existing record for an English criminal trial and going down in legal and Old Bailey history, probably made things go on for longer. That's more likely than one or more geniuses on the jury having the knack of brilliantly getting to the point very fast when barristers were beating around the bush and would have taken twice as long or not managed at all, and when even the judge didn't notice how good a certain question would have been. (Incidentally I wouldn't say this if the number of questions had only been 10 or 15.)
Nor do I think wanting to work longer days, which would have meant many other people working longer days too, in order to get the job done faster rather than slower, is something to be admired.
We should wish all the jurors strength in considering the evidence fairly and avoiding confirmation bias. Let it take as long as it has to.
I trust the refreshments served are to their satisfaction