Great Post
Danny some excellent stuff there. So good in fact I have copied and pasted that into my sound engineering book to be.
(Along with every post I have made too!) Sorry dude I own that now!

LOL
Danny has really helped me with my mastering too.
I do a lot of pre mastering prep in the editor. You can achieve about 20 to 30% of your mastering there before you even start mastering. After taming rogue peaks and things I can usually lift the rms level of the pre master 2 or 3 dB before mastering begins.
The better the mix the less the mix changes under mastered conditions, I am totally with
Danny on that one. If you are only working with great mixes often then this is not an issue for you as a mastering engineer. I send mixes back that change too much and they are usually quite wrong somewhere. My own mixes never change under mastered conditions. It is nice to be able to mix with mastering in mind. That
is the advantage of mastering your own mixes. You need the time off in between though.
Mastering stems is more common and I quite like it. I can usually do a better mix with the stems than the mix that comes in with the stems. I still master more two track material though by far.
I did sit in with a top Melbourne mastering guy once and while I did learn about the EQ and compression stuff I got a few other things out of the session I did not expect. First he used a lot of great reference material and he was switching to it quite regularly. All the levels have to be perfectly matched to make this work properly. It takes the speakers and the acoustics of the mastering environment out of the picture
to some degree.
(Quite a lot in most cases, anything that can push speakers and acoustics back a bit is good in my opinion) If you know how to use quality reference material you can master anywhere.
Also when doing the album he picked the biggest and best track and mastered it first and then used it as a reference in conjunction with all the other tracks on the album. This really helps setting the EQ for the other tracks using your first mastered track to compare them all to. This helps bring all the tracks together a bit more making the whole thing more coherent. I need VU's at least to get the level between tracks perfect. Ears are a good start but VU's can make it even better. VU's dance in a certain way too when the compression in your mastering is spot on. They definitely dance a certain way on well mastered commercial material.
The bass end is the thing that has taken me some time to get right. You have to do this. Everything else almost revolves around it. Too much bottom end ruins the rest of the spectrum and you will never get the rest of it sounding right. Once the bass end is sounding great everything else seem to fall into place a bit easier.