There are a few interesting things going for this card.
I'll start with the obvious - First, this is a card that effectively condenses 3 damage worth of attacks into a single action. If you're fighting an enemy with low fight but 3 toughness, this is going to help you clear it out in a single action. Obviously, this works best on Nathaniel Cho, who can turn it into a solid 4 damage without any external support. However, 3 damage is still good enough to handle a wide variety of normally irritating creatures.
Second, the effect is an isolated card that gives you a +1 for the first attack, and a +2 for the second. This isn't as large of a boost as something like Spectral Razor or Act of Desperation can give, but most Guardians have respectable to begin with - the +1 is enough for most easier fights, and the +2 can help make up the difference. In general, this will be as reliable as any 0 XP weapon.
Third, this is a Spirit card. The primary benefit means that it's something that you can find via Boxing Gloves, but it also means you'll be able to grab it with Calvin Wright, should you find you want more damage more than you need pure stats.
Finally, it is a Tactic card. The biggest benefit of that means it is available via Stick to the Plan, providing most Guardians with a low-price option if their weapons are not available.
It does have a couple of notable downsides. First, the attacks are broken into two separate fights. This means that you will need two draws from the bag to make that three damage land. You will only boost one part of things with commits or any other effects that boost the next skill check, and this means an additional chance to hit or some other negative token effect. Missing the first check is just as bad as missing any other combat event, though you can still get enough damage if you miss the second. If you were playing it specifically to deal with a 3-HP target, it does mean you can at least make a follow-up attack with a weapon.
Second, it's also a 2-Cost Event. Many Guardians have fairly limited income, and many guardians may prefer to spend their resources on a repeated-use weapon, rather than a one-shot event. Its price might be higher than some like.
Is this going to fit into most Guardian decks? While it's not a bad option on the whole, I suspect it's a little niche to be a top option for most. However, if you're using Boxing Gloves, if your hand slots are otherwise precious, or if you simply have the resources to warrant a bit more to deal 3 damage now and then, it's not a bad pick.