And I'm sort of glad to be wrong; Ted maneuvers John into buying jewelry for the missus.
Panel 1: We start with an exterior shot of a jewelry store. Ted's disembodied voice says that a pearl necklace would be perfect. When John's disembodied voice asks if he's sure, Ted says 'Absolutely.'
Panel 2: He advises John to get Elly something simple and elegant; as he looks in the display case, he says "That one, for instance, is quite lovely" about the necklace that seems the most appropriate.
Panel 3: Having chosen the Perfect Necklace, he says "Yes, that will do nicely" and asks the clerk if he can gift wrap it for his friend; the clerk says that it would be his pleasure.
Panel 4: As the clerk hands him his package, John thanks him.
Panel 5: As they walk back to the office, Ted tells John to trust him when he says that Elly will be thrilled that he chose and wrapped something like this himself.
Summary: What makes it funny is that while Ted came up with the idea and chose the right necklace while the clerk wrapped it. John gets all the glory. Funnier still, Ted knows Elly better than John does.