Re: Speeding up buddypress
It is compatible with shared.
The missed out stuffs — for example, APC. We can’t install APC on shared hosting. Even if PHP next version include APC as default extention, it will depends on the hosting site enable it or not. Without APC or other caching software, the best of W3TC’s performence has no chance to show.
For the rest of W3TC’s functions, such as minify, loading js,css, CDN, I prefer to do it manually by myself, because I will have more control on it and it’s easier to know where’s the problem if any.
I feel a bit lost at your questions of “How to pilot”.