That's quite clear to me. If I were to try my luck in the courts, I'd be pleasantly surprised if the Judge took the "basically" column as the legal interpretation. Ignorance, as far as I'm aware, is not an acceptable legal defence (as cited by many a judge to people who neglect to pay their taxes).
The fact remains however, few people read TOS pages or privacy polices. Any attempt to change that should be applauded in my view.
I would be very surprised if their legal department thought the "basically" column was a good idea. They can say that it isn't legally binding, but that claim isn't ... err... legally binding. Everything written in a contract is equally binding, and the proximity and one-to-one mapping could make the summary column part of the contract. If either party is surprised by conflicting claims, it will be up to the judge to decide which parts of the contract are stronger.
The "basically" column is a really bad idea. The "full" column should stand on its own. If they think it is too complicated, it should be simplified.
That is the most perfectly succinct explanation for why this might be a bad idea. Well done.
Be careful not to confuse criminal law with contracts. It is fundamental to the existence of a contract that both sides understand it. That is one of the few points of law that is pretty much a universal constant, whatever jurisdiction you're in.
(IIRC there must also be two parties (otherwise it is a deed not a contract) and the parties must have "capacity" i.e. the potential to fulfill their obligations)
IANAL - probably painfully obvious to anyone who is.
Law is like code (and magic) - it is a framework that gives real world power to abstract language - maybe this is why HN is so obsessed with legal chitchat
EDIT: fixed typo.
As always, IANAL.
Lawyers throw all kinds of language into a contract, that doesn't mean the intent was there. Vague, unfair, or overly broad language that was not clearly understood by both parties tends to get reduced, removed, or modified in accordance with what both parties reasonably understood to be the intent. So if they tried to get overly sneaky and do something where the basically version says X, but the full clause says we do X,Y,Z, then the courts may very well rule the implied intent was X but Y and Z were not implied and agreed to.
If they understand what they are doing, and plan to strictly abide by the basically section, this is a fantastic idea. If they at some point decide they want to get sneaky and put something in the detailed version that is not covered in the "basically" section, they may well find themselves in a world of trouble if it comes to court.
My experience was a company trying to sue me, despite them breaching the contract. The judge took a dim view of the crazy clauses in there and was pretty sharp with them. I expect the same thing would happen here. A normal user would probably abide by the "basically" section and the courts would probably take that interpretation. Of course YMMV.