Perhaps the most important use for the Engima/ULTRA intel was the feed back on the many deception ops. The Deception Committiee had ULTRA acess and used high level decrypts to track German reactions to the false information and adjust it. On the other hand Hitlers use of intel was so poor it may not have mattered
As Wiking and many others have observed less Enigma/ULTRA intel the more attention the Allied leaders pay to other sources, which in some cases may not be a bad thing. ie: Patton kept a balanced view of all his intel sources, & anticipated a German offensive in Dec 1944. Conversely the 1st Army G2 was overly dependant of ULTRA info, did not accept a OSS liasion, paid poor attention to reports from the Corps G2, ect...