Actually, I think "listing all the things wrong the the blood protection" is a cliché in itself...
Some of the obvious ones are:
It was supposed to be based on what his mother did to defeat Voldemort, and never claimed to work on anyone else. That means it was irrelevant when Voldemort didn't have a body, and became useless when he got a new one that bypassed those protections.
It doesn't have any effect on a house elf belonging to a death eater.
It doesn't reach beyond the house (or possibly the property line?), so an attack by (for example) Dementors elsewhere in the neighborhood isn't prevented.
It depends on Harry living under the same roof as his aunt. As Bluemage pointed out, fanfic authors have already pointed out that Vernon would hardly have been averse to selling Harry out.
That's just a few of the obvious ones. Again, listing all the flaws is a fanfic cliché of its own, there are many more than this out there.
Some of the obvious ones are:
It was supposed to be based on what his mother did to defeat Voldemort, and never claimed to work on anyone else. That means it was irrelevant when Voldemort didn't have a body, and became useless when he got a new one that bypassed those protections.
It doesn't have any effect on a house elf belonging to a death eater.
It doesn't reach beyond the house (or possibly the property line?), so an attack by (for example) Dementors elsewhere in the neighborhood isn't prevented.
It depends on Harry living under the same roof as his aunt. As Bluemage pointed out, fanfic authors have already pointed out that Vernon would hardly have been averse to selling Harry out.
That's just a few of the obvious ones. Again, listing all the flaws is a fanfic cliché of its own, there are many more than this out there.