Welcome to the forum!
Yes, this is normal behavior.
If the problem is that you can't see what you're doing, when you zoom out to see the whole thing, I can think of a couple of possible solutions.
1 -- Draw everything with a stroke width that you can see. Then at the last minute, before you send it to the cutter, change all the path width at once, to whatever your cutter requires.
Or 2 -- Draw everything with a stroke that you can see. Then at the last minute, duplicate everything (all at once). Change one of the copies to the narrow width that is required, and save the wider strokes on a hidden layer, in case you want to edit sometime later.
However, your last comment is curious, that you don't see this behavior with and older version 0.48. Have you tried every version between 0.48 and the current stable version? Or is 0.48 the last version that you used before now?
One possible issue that comes to mind, is I wonder if you might be drawing with the Pen/Bezier tool with a Shape other than None. Look on the control bar for the Shape dropdown menu and make sure it says None. If it's set for Triangle In or Out, then one end of each path goes down to a point. Those can be hard to see, even at 100% zoom. And they were not available in 0.48.
Another possiblity would be to double check that your stroke width unit is inches. Since everything else is set to mm, maybe you didn't realize that the width is in mm rather than inches?
Or we could examine one of your files, if you like. Personally, at the moment, I don't think of any other possibilities. But with more thought I might. And other people might have some ideas too.