The activist firm Elliott Investment Management has written to Honeywell International's (HON -0.06%) board of directors arguing for the conglomerate's breakup. The move follows a period of disappointing performance for the stock over the last few years: It's up only 4.8% over the previous three years compared to a 27% increase in the S&P 500 index.Is Elliott's move a catalyst to buy the stock?Time to break up, Honeywell?Elliott's central argument is that Honeywell's conglomerate structure is no longer suit ...