Why does Photoshop not remember any clipboard information?

I have a simple task to do. It's the sort of thing that crops up a lot as a professional graphic designer: client wants logo on all screen stills. Same place, bottom left corner. Best way to achieve this? Put logo in correct position on one design and add a one-pixel grey square to each corner. These will act as invisible position registers when I copy and paste the layer on to every other (57 and counting) artwork.

So, I just select all on that layer and hit Copy. OK, now open the next artwork and hit paste.

Nothing.

No paste.

The only way I can get copy and paste to work is to keep the source file and the target file both open at the same time and Edit/Copy every single time.

In my old version of Photoshop anything that had been copied stayed on the clipboard for me to paste, at speed, on 57 artworks one after the other, regardless of whether or not the source file was still open.

But now it wants me to copy a fresh version every single time. Terrible for productivity. Terrible.

And for those who wonder, yes Copy and Paste is by far the best way to work if an exact placement is required every time as dragging the layer over dumps it in a random place. Copy and Paste, when you have registration pixels, puts it in exactly the right spot every time. At speed.

So. Why doesn't Photoshop keep copied material in the clipboard any more? How can I make it remember Edit / Copy material?