Also another good practice is to tweak overall processing first and then - let BS.412 limiter adjust the level but only gently. It's never a good approach to let BS.412 do all the heavy lifting in gain reduction, while having balls-to-the wall settings in MB.
Actually I get quite decent results using the current BS.412. And you'd be surprised how much post MB gain or simply attack/release and treshoulds for highs and bass can affect BS.412 limiter's behaviour. The changes can be quite dramatic when MB isn't tweaked properly in the first place.
With the +3 dBr limit we have now in Poland I can adjust processing to stay within 2.0-3.0 (usually 2.5 for
most content) with no ducking or noticable bass/highs cut-off's. Increasing headroom and dynamic range in BS itself helps as well.
Having said that - consider this as just a little hint from a "noob".
http://www74.zippyshare.com/v/b9QoEe6c/file.html
(Bass and highs limited to some greater extent in MB, yet it still appears heavy, while standing well within limits).
this is one of the worst I caught, so still room for improvement in my preset

:
dBr's are just the numbers - you can't exceed'em, but on the other hand - there's abolutely no need to push, for example +3dBr sharp all the time, especially when the content is extremely variable. Better keep it swinging somewhere around target and even -1.5 from it (from time to time). When it sounds better that way, then why not? For instance, you can always stick to some arbitrary loudness level instead, like ITU BS.1770 - I definitely get much better consistence when sticking to this one, rather than dBr units. Just imagine a situation where on a hitlist a new Adele track follows some Calvin Harris remix (or the other way round) - not going to work well with dBr's strictly limited (or maxed out).