I'm sorry to disagree with a Rav, but
to not look at the screen when pumping is potentially placing
oneself in sacanah - an issur doraysa.
vs "looking at the window on the pump" battery powered - an issur
drabanon.
if chas vsholom someone underboluses, or even worse, overboluses,
then a persons life could be in danger. PLEASE LOOK, or
perhaps the Rov does not understand all the issues - he could
call me or call Rabbi Meisels just to be sure that he understands.

I went to a shiur sponsored by national Agudah, where we asked
shailos to Gedolei Yisroel. One question was what to do when a Rav
paskened against standard medical advice (such as not having breast
surgery when a women had biopsy proven breast cancer!), the advice was
to explain it to the Rav. (in that case, the Rav called back the woman and
asked her why she did not schedule the surgery sooner!).

if you do not look at your hands when pulling the trigger of a loaded gun
while it is aimed directly at your head (chas vsholom), is it any less
dangerous? of course you would never do that, so of course, you would
never overbolus yourself on insulin. why take a chance? that is an issur
doraysa. The Brisker Rov was once asked why he was meikil (lenient) in
issurei Shabbos when it came to potentially life threatening situations. He
replyed that he was not meikil in hilchos Shabbos, but he was machmir
in hilchos Pikuach Nefesh (saving lives!)

B well
and gut voch!
P