Quit safari, then, in the Terminal, enter the following command:
defaults write com.apple.Safari WebKitResourceTimedLayoutDelay 0.0001
Make sure you also implement the previous hint; for sake of convenience, the command in that hint was:
defaults write com.apple.Safari WebKitInitialTimedLayoutDelay 0.25
Warning: If you don't have a fast machine, you may want to increase the numbers, instead of 0.0001, try 0.05, 0.1, 0.25 or 0.5...

　据说跟firefox有的一拼
　robg adds: There was some discussion in the comments to the original hint regarding the exact format of the defaults write command and whether you needed the -float flag. The man page for defaults seems to state that you do not:

　For the basic plist types (strings, data, ints, floats, booleans, and dates) it is not necessary to precede the value with a type qualifier. For example, the following commands are equivalent:

　defaults write somedomain preferenceKey 500

　defaults write somedomain preferenceKey -int 500

　So the commands in the hint should work just fine without the -float.]

　测试的机器是 700MHz 的 iBook G3，用之后页面有明显的加载速度提升，但VersionTracker等某些站点会经常出现页面无法显示的错误。
　另外，苹果给出的有效值(默认)的下限应该是0.25，作者给出的0.0001比较夸张，G5以下的机器就不要设那么小了。