Whilst I sort of agree with what you're saying in general, and great that you took the time to help a poster out, my point is you can't "force" someone to agree to something after they've already taken an action they have every right to believe would not force them into an agreement.
Disclaimers are not widely used here so the OP had no reason to believe you'd force him to agree to something just by reading text he had no reason to believe carried any conditions.
Sure, make it clear that your "advice" isn't advice but opinion (lets face it, calling it a novelty post is clearly not the case, you genuinely are offering the OP advice) and not to take any action based on it because you could be wrong/don't know al the facts / whatever. I just don't believe you can in anyway enforce that a reader "agreed" to anything if you don't tell them they are agreeing to something until after the fact.
Ok, in your case it's harmless, it just seems like using legal jargon to bamboozal readers into agreeing to something which they may not have. Perhaps I'm just being sensitive to the "you agree by reading" after the fact which seems a bit off to tell my that I agreed to something when I'd already done it.
By the way, as I have replied to your post, as per my standard terms and conditions (available on request) you have agreed to incur a charge of 3 units of my time equating to a further £3000. This making people agree to stuff when it's too late to disagree is great, I may add this to my sig and be able to retire by October!!
*note* I am just kidding, nothing in this post is intended nor given as legal advice. No warranty nor indemnity is given as to the accuracy, suitability or any other facet of this post.
By reading this post you agree that I shall not be liable for any and all direct and indirect losses including but not limited to damages and loss of profits as a result of this post. This post is given purely for novelty value and I in no way recommend that anything in it is taken as any sort of advice or acted upon as if it were. In any legal matter I suggest that you seek adequate legal advice. Your mileage may very. Terms and conditions apply. Approval subject to status. The value of your house may go down as well as up. It may rain tomorrow, that's not my fault either.