I think, of the trio (Sickle, Rod, Pentacle) this one might have the best value for most mystics. Always having a way to bail you or an ally out of an incoming attack is pretty nice. No, it doesn't solve problems, but the flexibility is very nice.
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A fair number of Aloof enemies care about being exhausted.
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You can bail your fighter out of getting whacked without taking your eye off getting clues.
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You have something to deal with enemies until you find your big damage spell.
That said, doom is really bad unless you want it for some reason OR the agenda is about to advance anyways. Saving move and engage actions won't count for much if you cost your entire team a turn. It might be worthwhile to reserve some skill cards for some certainty on that "succeed by 2" check.