More info
First of all I couldn't pull up the link. But I can speak about looking for cracked cylinders.
Some one put out some iffy cylinders that had an AD against them, and although the compression test was part of the inspection, it was not the only thing that had to pass. In addition, the pistons was brought up from BDC, pressure in the cylininder, and soapy water applied outside looking for cracks. Also be aware that what a compression test determines is how well the running parts of the cylinder are working. It "might" find a crack. Internal pressures can be up arround 800psi (I think). between that and the temperatures, the joint between the steel cylinder barrel and the aluminum head are severe. The cracks that could develope may not leak much until it lets go; Bright light, vanity mirrors, look for exaust stains or fretting cracks. Nore often than not, it's from a spark plug hole.