Cosa pensate di questo codice ( fonte ):

# 1 YEAR
<FilesMatch "\.(flv|ico|pdf|avi|mov|ppt|doc|mp3|wmv|wav)$" >
Header set Cache-Control "max-age=29030400, public"
</FilesMatch>

# 1 WEEK
<FilesMatch "\.(jpg|jpeg|png|gif|swf)$">
Header set Cache-Control "max-age=604800, public"
</FilesMatch>

# 1 WEEK
<FilesMatch "\.(txt|xml|js|css)$">
Header set Cache-Control "max-age=604800"
</FilesMatch>

# NEVER CACHE
<FilesMatch "\.(html|htm|php|cgi|pl)$">
Header set Cache-Control "max-age=0, private, no-store, no-cache, must-revalidate"
</FilesMatch>

Per quanto riguarda 'Remove render-blocking JavaScript' di Google PageSpeed, qualche dritta per risolvere il problema ?