I actually think this was a good move by Boston. True Mondesi is injury prone, but he's a former top 5 prospect who is still only 26, plays good defense at SS and other positions, has elite speed, and despite the sub .300 OBP he has still posted over a .700 OPS the last 4 seasons (excluding last season when he barely played). Obviously the key with him is health, but this was a high reward low risk move.