IANAL (but my wife has a JD): it's a fine line; on the one hand, the legal principle of "meeting of the minds" might make the judge rule that the "basically" illustrates the true intentions of the contractual clauses. On the other hand, as you say, judges are often unsympathetic to pleas of ignorance. What you sign in the contract is generally the contract. Most of the time, what this probably means is that judges will take the "basically" summarized version when they feel the contract is egregiously inequitable, and otherwise defer to the legally binding wording.

EDIT: fixed typo.