Learn English – What does “that’s you all over” mean

It doesn't mean it's an important thing; in fact it's sort of the opposite. What Ronan means is that he wished they learned more than "a bit", but he's glad they're at least learning something. He might have said instead "Well, that's better than nothing."

This is generally used when you wish something more/better than what is happening were possible, but are accepting what you can get. For example:

Jim: "Did you get everything we needed for the party? Sally really wanted those special crackers she likes."

Mary: "They didn't have those, but I did find paper plates with unicorns on them!"

Jim: "Well, that's something. Sally does like unicorns."

Wherein Jim really wishes Mary had gotten the crackers, but is pleased that at least something Sally likes will be present.

The primal meaning of the phrasal verb "to get by" is "to be ​able to ​live or ​deal with a ​situation with ​difficulty", so according to the rules both Seth and Georgie conform to, they got used to not mentioning Neal's name in the conversation.