Performance cylinder wall preparation has always been a multi-step process. If you have ever tried to polish raw metal, do a show quality "no flaw" paint job or do furniture quality woodworking, you know that you have to do sanding in steps, using a finer grade sandpaper for each successive step, to achieve a finish that shows no scratches. Today's technology is just more exacting than what was available 25 years ago (even five years ago!). The "plateau" finishing that is referred to is an application of technology to achieve a super-fine cylinder wall finish with no burnishing. A web site that will introduce you to the basic understanding is from the Sunnen corporation:
http://www.sunnen.com/newsDetail.jsp?id=5&catId=42&flgArc=
There are CNC block preparation machines today that are capable of boring blocks off factory blueprints and finishing the cylinder walls to a programmable selected finish while sensing the hardness of the block and cutting quality of the honing process as it is running. Stone selection, speed of the honing head, oscillation rate (moving the honing head up and down the cylinder), and stone pressure are all controlled by the machine to produce the requested finish. Of course, you pay for the technology when you take a block to a shop that has one of these machines (inquire in the NASCAR circles), like $1000 to blueprint a block. But that goes back to the old saying, "You get what you pay for".
