tcsh being dodgy, or pipe code ishoos?

Anyone with insight into this?

(jmallett_at_big-lizard:~)39% ( echo 1 ; ( ( echo 2 ; echo 3 ) | xargs -I% echo + % ) )
1
+ 2
+ 3
(jmallett_at_big-lizard:~)40% ( echo 1 ; ( ( echo 2 ; echo 3 ) | xargs -I% echo + % ) ) | cat
1
+ +2
3
(jmallett_at_big-lizard:~)41% ( echo 1 ; ( ( echo 2 ; echo 3 ) | xargs -I% echo + % ) ) | cat
1
+ +2
3
(jmallett_at_big-lizard:~)42% ( echo 1 ; ( ( echo 2 ; echo 3 ) | xargs -I% echo + % ) ) | cat
1
+ 2+
 3
-- 
juli mallett. email: jmallett_at_freebsd.org; efnet: juli;