Buck regulators often specify the value and placement of the output capacitor. Typically 10µF placed very close to the buck regulator.
However, what would the effect be of replacing the 10µF output capacitor with 10x 1µF capacitors. Where only one of those are placed immediately at the buck regulator, and the other 9 are decoupling capacitors at the load. Within an inch or so from the buck regulator.
The 1µF capacitor close by the buck regulator should handle the high frequency components of the buck switching just as well or better than a 10µF would, and the total capacitance is 10µF so the regulator loop should function properly.
For point-of-load buck regulators, this distributed output capacitor approach would have quite some practical advantages nowdays when 1µF is readily available in 0402 footprint.
Is there a downside which I am not seeing?
Clarification 1: The current at the output of a buck regulator is DC plus a small triangle wave at the switching frequency (typically 1-2MHz). Triangle waves do not have any significant HF content. Examples can be found here: http://electronicsbeliever.com/sizing-the-inductor-of-buck-converter-and-setting-its-operation/
Clarification 2: Physically smaller capacitors have lower ESL (which is better). See for example: SMD capacitor package size and high frequency performance