<VV> VirtualVairs Digest, Vol 46, Issue 68

[Smitty Smith]

I got a kick out of this.  I haven't ever heard of anyone grabbing a cylinder and squeezing it while the engine was running.  Nor do I believe that small a distortion will affect ring sealing.  Nor do I believe that clamping a cyl with a plate while boring/honing will gurantee that the cyl will take on exactly the same shape when it is clamped onto an engine.  If it was that big a deal then we would have lots of "new rebuilds" that the rings would only seat in after thousands of miles.  CIC  Since you still are not convinced, please perform this simple bench 
 experiment. Take a newly bored cylinder and place it on the work bench.
Then place an inside micrometer across the bore, opening the micrometer until it just 
supports itself across the bore.

 Now, without disturbing the micrometer, place your hands outside the
cylinder 90 degrees  from the direction of the micrometer and squeeze the cylinder 
 between your hands. You will find out that the little pressure from your
hands will distort the cylinder and allow the micrometer to fall out of the
cylinder where you placed it.