thinking of my old Lofgren blanket I see absolutely no conceivable way that it could attribute to increased trans temps. I'd still run it if the rules didn't require more for sub 10 passes.
I used to have a Lofgren blanket in the cuda before I went to the CSR shield. Never had a problem w/ either one, but I don't have a trans temp gauge either. The Lofgren blanket is pretty small...really doubt it would cause a heat issue.