Here is where you read that:
http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 0778366317
The low end Colnagos did not have trefoil markings. The Sport and the Export were two examples, where the Colnago logo and name does not appear anywhere but on the decals. The same goes to low end MTB frames, like the Maxim and the "de luxe"
The Super Sprint had a cutout in the bottom bracket, a trefoil in the headtube lugs, and the word Colnago in the seatstay caps.
Later model frames replaced the cutout in the bottom bracket with an embossed Colnago emblem. The late 80s Duall was the first one I know that did this, and by the early 90s the cutout was gone.
If a frame does not have trefoils or the name stamped on it, then it is a sure sign that production has been outsourced. The Taiwanese made 2010 "Super" singlespeed monstrosity that Colnago sold is such an example.