This is a truth. Though we now have reference files here, which will help when you get them in alpha 4 xxx
Not threading so much as I don’t know that there’s any gurantee that a particular algorithm can cope with the source buffer being overwritten (because I haven’t been writing these). For this to be safe, all the data needs to be copied out and processed before being written back, otherwise weird things might happen. I suspect this is generally going to be the case, but I don’t know if it’s a cast iron design promise.
In this case, because the source and destination buffers will always be the same size, it’s very unlikely to be a problem. With something like PCA, you’d probably need to try and see if everything explodes…