Why blocking DC for differential output

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b_force

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A common thing seen in many DAC outputs is a ugly (big) capacitor to block the DC offset (+2.5Vdc in general)
However, many DACs have a differential output.
Lets assume we use a differential to single ended converter (opamp or so).
Than the output DC offset is going to be zero (because both input are +2.5Vdc and therefore cancel each other out).
If there is more than enough headroom (say ±15Vdc voltage rails and 3.5Vpeak output sinus), what would be the problem just removing these DC blocking capacitors?
I don't see any reason for using them in this case?
(also because the Vref of both outputs is the same)
 

Yes a balanced/symmetrical power supply is used.

No, not resistors INSTEAD of a capacitor.
It's about the principle.
As far as I know the DC voltage is cancelled out.
Nevertheless you see this DC blocking capacitor in many designs???
 

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