Most people that claim that P2P meth is somehow chemically different from pseudo meth have neither any chemistry education, nor a means to determine the synthesis method, nor an explanation for the actual difference in structure or composition. In fact most of them don't even know for certain whether their meth is racemic or not, don't know how to determine it, and are unwilling to spend the small amount of money on a polarimeter or invest the time and effort into learning to use it (which would provide a reliable answer, costs less than $100, and a high school student can learn to read it in an hour or so).
Also they neglect to note that P2P meth is by no means new; it was quite common before the 90's or so, and nobody had any complaints back then.