I guess the clinical relevance depends on how well you can tailor treatment based on it. AFAIK if docs don't know a) the specific bug and [1] b) its antibiotic resistance and c) the patient is seriously or potentially going to be seriously ill they start out with broad spectrum anyway.[2]
Since the fingerprint technique doesn't tell you antibiotic resistance the real benefit is probably identifying rare bugs early and to some degree avoiding broad-spectrum stuff and slowing down the sort of antibiotic resistance bacteria develop over a population over time.
[1] Docs can genrally guess the type of bug, or at least the class of bug, and even "narrow-spectrum" antibiotics can cover multiple classes
[2] For less serious infections docs go by likelihood tables and population features (ie-- UTIs are generally killed by X in this region of the world/country). If that treatment fails, they try another one.
