[Exim] Default retry rules to aggressive?

Hello,
I am just wondering, exim uses
F,2h,15m; G,16h,1h,1.5; F,4d,6h

i.e. retry every fifteen minutes during the first two hours.

Isn't this rather aggressive (the rfc suggest at leat 30 minutes) or
is this the rule that came up after years of experience as a good
default?
                 cu andreas
--
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