filuhzwawy wrote:any successes on the russian theater
Yes - you can try and Google for TM30-430 (I think, someone correct me please if that is wrong), the 'Handbook of Red Army Forces', published by the US War Department from 1946 onwards. There is an online version floating about somewhere. It is a distillation of Soviet material and tactics, based on Gehlen's work.
It seems Gehlen also correctly forecast the attack on the Rshev balcony in November 1942, enabling preparations that led to the defeat of the Red Army's attempt to cut it off. He failed to predict the attack on Stalingrad though, and later in the war failed to predict the Iassy-Kishinev operation until it was too late. (Glantz' paper on Iassy has the intel situation laid out, and Kissel's 'Die Katastrophe in Rumaenien' contains the Feindlage information confirming this, IIRC).
A major disagreement with Hitler's view of the state of the Red Army seems to have developed towards the end of the war, when Gehlen was right about the likely number of Soviet divisions, but wrong about the manpower levels. Hitler seems to have had the right inkling on the manpower, but seems to have underestimated the number considerably, leading him to underestimate the threat posed by the Red Army in 1945. Not quite sure where I read that, or how correct it is.
After the war Gehlen built up the German secret service again, it was first called 'Amt Gehlen'.