"Pad it out" VERSUS "Plump it out"

[Tom]

Hi

Could you please tell me if both mean the same thing?

1- Your answer/ explanation is good but I would like to pad it out a bit.

2- Your answer/ explanation is good but I would like to plump it out a bit.

Tom

[Mister Micawber]

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To me, pad asks for redundant bulk; plump asks for more meaningful addition.
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_________________
Canadian-American native speaker
who teaches English for a living at Mister Micawber's
ESL cafe: Interview with Mister Micawber