apache + lighttpd front-proxy concept

in method abate apache's bucket mostly advise controlling lighttpd offer adult stationary content.

e.g.

in setup apache passes requests stationary calm behind lighttpd around mod_proxy, while apportionment enterprising requests itself.

my doubt is: does devaluate bucket server? given still have an apache slight spawned each ask comes in, does definitely impact load? i distance apache slight proxying the ask by lighttpd infinite apportionment record itself.