Linked furnishing changing alignment?

Danikat

I'm trying to place a whole load of books on shelves in one of my houses. I know there's a number of reasons that doesn't work well, but I've encountered one that's new to me. To get the books lined up neatly I'm arranging them into rows in mid-air in the room (so I can see them from all angles) and linking them all together so I can move the row around. I keep finding that when I've re-positioned them they're now out of alignment, specifically the one all the rest are linked to which has shifted.

For example I'll have them at head height to make sure the bottom of each book is in line (so they'll all sit on the shelf together), then I move them down near the floor so I can get a top-down view to make sure they're all facing in the right direction. I'll change only the one on the end (because I've already aligned all the rest) and then when I move them back up to head height I find the book all the rest are linked to is higher up.

I'm only editing the end book, the rest are just moved as a linked set to change the view, so there's no reason their alignment relative to each other should change, but it's happening at least every other time I move them which is really annoying because then I waste a lot of time fixing the mistake (which often involves unlinking and relinking them).

Is this a known issue? It would be nice just to know I'm not going mad and imagining it, but if there's a way to prevent it that would be even better.