Here are a few of my thoughts...
First, not all tool marks are desirable. There are marks made by an experienced hand with quality tools and then there are marks made by those less skillful. The results are very different. An example is faceted background of carving versus torn grain or corners of chisels digging in during the wood removal.
Not all scraping is equal. Some can be very coarse and heavy, while at the same time it can be done very delicately such that very fine finishes can be acheived. Each can be nice depending on what you are trying to acheive and personal taste.
Tool marks can add a great deal of visual interest in my view. I've made guns finished to an extremely fine level. Some of these have turned out well, but I think some have been a little too sterile.
Leaving tool marks is not necessarily a shortcut. For example, I can create a very smooth background when carving by using abrasives easier than I can create a faceted surface from chisel cuts or scraping.
Jim
