Process refinement usually deals with thickness, gateox thickness ild thickness, things you can tweak while still using the same feature size.(gate length etc etc)
A process shrink is when you shrink down the lines etc to a smaller average distance, this is a major thing and usually requires retooling and a reassignment of control parameters.
If my control target is .5nm and I have an upper control limit of 6 and lower is better, if all of the widgets I make start to always hit below 5(if one goes over 6 I look for a problem in my line).
Once all of the controls hit their targets and start exceding them, I can then lower the targets, thus when a widget has a 5 now(which was my target before but now its say 4) I will begin to look for a root cause of the problem and remedy the issue, this overtime causes refinement of the process.
INtel claimed that amd had .13micron CLASS gate lengths, that is their.18 micron gate lengths were below what you would expect to find for a .18 micron process and were at the levels you would expect for a .13 micron process. Now if dresden were designed from the ground up as I have heard to be a .13 fab, then there is ample reason to conclude that the gate lengths which were small were a result of the improved etching and thinfilms process that dresden had, rather than a concious effort on amds part, which is extremely believable.
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A process shrink is when you shrink down the lines etc to a smaller average distance, this is a major thing and usually requires retooling and a reassignment of control parameters.
If my control target is .5nm and I have an upper control limit of 6 and lower is better, if all of the widgets I make start to always hit below 5(if one goes over 6 I look for a problem in my line).
Once all of the controls hit their targets and start exceding them, I can then lower the targets, thus when a widget has a 5 now(which was my target before but now its say 4) I will begin to look for a root cause of the problem and remedy the issue, this overtime causes refinement of the process.
INtel claimed that amd had .13micron CLASS gate lengths, that is their.18 micron gate lengths were below what you would expect to find for a .18 micron process and were at the levels you would expect for a .13 micron process. Now if dresden were designed from the ground up as I have heard to be a .13 fab, then there is ample reason to conclude that the gate lengths which were small were a result of the improved etching and thinfilms process that dresden had, rather than a concious effort on amds part, which is extremely believable.