Oh my, yes. If you want to be a good designer, you must know how the printing process works, and then create to that end.
Your clients will need to know how much things cost, so you need to to be aware of how much each and every item involved will affect the end cost.
You need to keep in mind what other processes might be used down the road, such as signage, silkscreening and TV, and then design so this can be accomplished more readily.
You need to know how different papers act when used for different inks, embossing, cutting, folding, stitching, laminating, displays and archiving. You need to be aware of how ink colors change on different colors and types of stocks. You need to understand 4 color process v.s. spot color printing, and if using high speed color printers/copiers you need to understand how colors reproduce on these, and how they differ from each other.
If your clientelle can’t afford high end printing, you need to know how to create a high end design and how to reproduce it to make the best impact using less costly methods.
There is more, but I think you get the idea. Producing good design is a complicated business if it is done correctly. Anyone can draw a logo. But not everyone can put together a company presentation and predict cost and quality, and then design to meet all the needs of presenting that logo.