Note 4 was in the 2000 D1.1. Although academic at this point, to answer your question, it was intended for both material grades, as Doug indicated. I got curious about any notes prior to the revision to the 2002 edition, and found this:
In the 1980 D1.1, the note read: "Only low hydrogen electrodes shall be used when welding A36 or A709 Grade 36 steel more than 1" thick for bridges".
In the 1992 D1.1, the note read: "Only low hydrogen electrodes shall be used when welding A36 or A709 Grade 36 steel more than 1" thick for dynamically loaded structures".
In the 1998 D1.1, the note read: "Only low hydrogen electrodes shall be used when welding A36 or A709 Grade 36 steel more than 1" thick for cyclically loaded structures", which is the same note that is in the 2000 edition.