Is this subject a Gerund? Verb/Subject Agreement

[Evalc]

The other day a quote came up in class by Peter F. Drucker: "Doing the right thing is more important than doing the thing right."

Or so it was supposed to be. They actually wrote it out like this: "Doing the right things is more important than doing things right."

I am reasonably certain that "Doing" in either case is a gerund. I know that most gerund subjects only take singular verbs, although I recall there being a few exceptions to the rule.

My questions are, is "Doing" here a gerund? Or is the sentence itself grammatically unsound? If "Doing" happens to be one of the exceptions, then should the linking verb be "are" instead of "is"?

I'm asking about the version of the quote that came up in class rather than Drucker's.

Thanks.

[Cerberus™]

"Doing" is a gerund in both quotes. All instances of "thing" and "things" are objects to their respective gerunds. "Doing" is simply singular in both quotes, the finite verbs "is" must be singular, as they are. Both sentences are perfectly sound.

Perhaps the plural gerunds you are thinking of are of this kind: "the beatings that this child endured have killed many an adult". However, I'd never call "beatings" a gerund here: in this sentence, "beating" is an ossified gerund that is a gerund no more; it has become a noun. Otherwise, I cannot think of a plural gerund. I doubt whether there are any. The same applies to the following words. They can be either gerund or noun, depending on context; where they are plural, you may be sure they are nouns.

beginning
feeling
meeting
setting
turning
being
finding
offering
showing
warning
building
hearing
painting
sitting
drawing
meaning
saying
suffering