Your claim paraphrased.
It is as easy to get a group of competing people to agree to a lie as it is for one person to lie.
That defies logic.
That defies logic.
If only logic applied. Peer review, especially in the age where government funds 90% of scientific research, is not "competing people". It is far more likely to be "cooperating people" (like Democrats and Republicans behind closed doors a appropriations committee, each signing off on the other's earmarks.) These guys basically review each other's papers and fund each others grants. They scratch backs.
I think you have an idealized view of how the peer review process works. Here's a blog discussing the issue in general--- read down to the comments.
The peer review process is not working in areas where there is big money involved. The blogs have some suggestions on how to fix it which boil down to breaking up the "old boys clubs" that the review committees have become and making the process more open to outsiders.