As a side-note, wasn't it MacLaren who wrote The Perfect Batsman, a biography on Jack Hobbs?
Barnes was indeed a difficult character. In the first Test of the 1901/02 series, Australia found itself on three for one in response to England's 464 when Trumper pushed back a Barnes slower delivery. The bowler caught it casually, one-handed, provoking a rebuke from captain MacLaren.
"Well," Barnes protested, "I caught it, didn't I?"
That is probably a rather poor example of Barnes's stubborn nature, but it's the only one in which MacLaren was involved that sprung immediately to mind. Roland Perry, whom I seem to be quoting quite a lot lately, passes this judgement on their relationship: "MacLaren, an amateur, was one of the few men in the cricket establishment who knew how to handle this dark, brooding figure. There would be no forelock-tugging or 'sorry sir' from this straight-backed Staffordshirian."