Usually with a CAD program like RealCADD, and many other Mac CAD programs (like the old ClarisCad for example) you set your scale to suit the eventual printed page – just like you would if you were doing a drawing on a drawing board. Then you don't have to do any re-sizing to print. With RC you can zoom to any amount, so there is no difficulty seeing what you are drawing, even if the scale is quite small. I often draw at 1:50 for example, but RC is so accurate at any scale it's never a problem.
The US has a problem in that its paper sizes are not at a consistent ratio – so resizing is a problem. With international A-series, or B-series, that is never a problem because each size is at a constant aspect ratio (√2). So for example, if you fold an A0 sheet in half you get A1; fold that in half and you get A2 and so on. Letter, Legal and Tabloid (11 x 17) just don't have this consistent advantage; nor do US Arch paper sizes.
So, in the US it is particularly a good idea to set your scale to suit the eventual paper print size. For example, I make a lot of my drawings to suit 11" x 17" landscape (which also prints out OK as A3 in the rest of the world) and before starting a drawing I decide a scale so that what I am drawing will fit a piece of paper that size; so I might use 1:10; 1:20; 1:25; 1:30; 1:33.33; 1:50 and so on, depending on the size of object – mostly boats – that I am drawing.
Then you never get scale problems with dimensions or anything else. And the actual scale of your printed document will be a sensible one – one that exists on a scale rule for example – or can be measured using a builders tape. Drawing at (say) 1:1 and then rescaling to fit a printed page tends to produce impractical scales for the end user if they want to measure something from the drawing.
If you do do a resize (which is absolutely not a good way to change the scale) – you can set the new scale of the drawing in the Layers pallet. So any new bits will be at the new scale. A much
better way really is to create a new layer (or even a new drawing) at the scale you want and then cut (or copy) and paste the objects from the original layer to the new layer, at which time they will automatically rescale (if you answer "Yes" to the dialogue that comes up –see manual http://www.whisstock.com/realcadd/page_05.php?page=05&page_id=05_02
I do agree with you that it would be nice if RC registered changes from portrait to landscape, which would save hitting the *1 keys twice.
And a checkbox to link the resize data would also be nice. Though I have to say that I often resize by unequal amounts
– to alter the characteristics of a curve (or polyline) or similar. You can make it shallower by resizing the x-dimension more than the y-dimension for example.
I think I will write a new bit of the manual to deal with scale!
Cheers -- George