How to create links to Previous and Next posts

Question about loop efficiency:

At the end, you run through the entire loop to display two posts. Since the entire loop could consist of hundreds of posts or more, could it be more efficient to simply create new loops for each of the two posts like this?

<Loop type=post id="{Get prevID}">
  ...display stuff ...
</Loop>
<Loop type=post id="{Get nextID}">
  ...display stuff ...
</Loop>