by cgentry Thu Aug 11, 2016 2:47 pm
I don't think the first one is suspect, so much as it just makes a sentence that wouldn't make much sense. I think both sentences you've quoted are NOT gerund examples. Each is an example of a noun (Mike) with a noun participle modifier (swimming).
This is opposed to the possessive modifier (Mike's) gerund (swimming) constructions in the other two sentences used in this set of examples.
In the sentences you've quoted, Mike is the noun, and swimming is a participle modifier -- not a noun.
So, "I like Mike swimming" means that you like the swimming Mike, but not other Mikes. It's grammatically correct, it's...just not something that would make sense in real life.
"Mike swimming is a sight to behold" uses the same construction. The "swimming" is not a noun, it's a participle modifier describing which Mike is a sight to behold. He's a sight to behold when he's swimming, but otherwise, he's not that impressive. This is a sentence that could work in real life.
It's more a meaning distinction between the two versions, not a grammar distinction. Notice that the parenthetical explanations in the Strategy guide both italicize Mike as the noun, not the swimming.