Multiple parallel capacitors should be modeled with their parasitic inductance at the very least. One capacitor will resonate with the parasitic inductance of the next capacitor to produce amazing peaks and nulls in the total bypassing of the undesired noise.
Usually, the old adage of paralleling multiple capacitors of different value are likely to produce LESS, and very frequency dependent affects on the performance.
One trick is to add series resistance to each capacitor to De-Q the parasitic unwanted resonances.