BASH_SUBSHELL count not counting?

[Roger]

Within GNU Screen session & VTE:

roger@localhost2 ~ $ bash

0 ;-)
roger@localhost2 ~ $ ps -ax |tail
Warning: bad ps syntax, perhaps a bogus '-'? See http://procps.sf.net/faq.html
30840 pts/6    Ss     0:00 /bin/bash - /home/roger/bin/bashnoprofile_ionice.sh
30842 pts/5    S+     0:00 bash --noprofile
30844 pts/7    Ss+    0:00 su -
30845 pts/6    S      0:00 bash --noprofile
30848 pts/8    Ss     0:00 /bin/bash - /home/roger/bin/bashnoprofile_ionice.sh
30849 pts/8    S+     0:00 bash --noprofile
30920 ?        S      0:00 [kworker/1:2]
30981 pts/6    S      0:00 bash <-- New bash shell within a bash shell
30995 pts/6    R+     0:00 ps -ax
30996 pts/6    S+     0:00 tail

0 ;-)
roger@localhost2 ~ $ echo $BASH_SUBSHELL
0

0 ;-)
roger@localhost2 ~ $ exit
exit

0 ;-)
roger@localhost2 ~ $

-- 
Roger
http://rogerx.freeshell.org/