The funny thing is its not transitive. No slowdown if you invoke bash specifically with a new shell.
% rm /tmp/test.sh ; echo $'#!/bin/sh\necho Hello' > /tmp/test.sh && chmod a+x /tmp/test.sh
% time bash /tmp/test.sh && time bash /tmp/test.sh
Hello
bash /tmp/test.sh 0.00s user 0.00s system 83% cpu 0.004 total
Hello
bash /tmp/test.sh 0.00s user 0.00s system 77% cpu 0.003 total
vs the one from the article:
% rm /tmp/test.sh ; echo $'#!/bin/sh\necho Hello' > /tmp/test.sh && chmod a+x /tmp/test.sh
% time /tmp/test.sh && time /tmp/test.sh
Hello
/tmp/test.sh 0.00s user 0.00s system 2% cpu 0.134 total
Hello
/tmp/test.sh 0.00s user 0.00s system 73% cpu 0.004 total
(edited for formating)
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