At first, I couldn't find anything diagonally, but that's because the message begins with unusual words that I didn't see at first. Instead, I noticed quite a few I's and O's, so I went about trying to put them together with T's and N's to make "TION". Then, I was able to make "OPERATIONS" diagonally in the lower right corner with only horizontal shifts:

Row 1 - ?
Row 2 - ?
Row 3 - Left
Row 4 - Right
Row 5 - Left
Row 6 - Left

which results in the bottom 4 rows as such:

STERPIDO R
FVOITDI EI
AFTANS PTN
ELCAI OAOS

Next, I noticed the next word back ended with ISIO_ and I guessed the final letter would be N, so I shifted Row 2 to the right.

Row 1 - ?
Row 2 - Right
Row 3 - Left
Row 4 - Right
Row 5 - Left
Row 6 - Left

which results in the bottom 5 rows as such:

IHSUMLOI N
STERPID OR
FVOITD IEI
AFTAN SPTN
ELCA IOAOS

Finally, I decided to shift Row 1 to the right to make DIVISION

Row 1 - Right
Row 2 - Right
Row 3 - Left
Row 4 - Right
Row 5 - Left
Row 6 - Left

BTIHSUINV
IHSUMLOIN
STERPIDOR
FVOITDIEI
AFTANSPTN
ELCAIOAOS

Message:

Bit shifts have use for multiplication and division operations.