Ok, as for the quality volume you should check the ET blog of yours and search for the old explanations I gave you for that. But I'll give you a run-down.
1. Reps should be 1 to 3 but no more than three. My thinking on that is three is the most you can do, while lifting heavy and still call it QUALITY. By that same token 3 is getting up there so if most of your sets are singles or doubles that would be perfectly acceptable.
2. If I gave you a set of guidelines about how to go up or down then it would be "Eric's" quality volume any more.
3. You have to slowly build up to around 80 percent or so of max. You just did 415x5 so if you just call "max" 415 that will be a good place to start. So warm up and then acclimate to a double or triple of around 80% of that.
4. Take a little time between each rep and give yourself a chance to "decide" if you done with the set or not. SO this is very much a "percieved effort" thing. Assuming you hit your first triple at around 80% and that should be easy, right? So put on 5 OR 10 pounds depending on just how easy it is.
Then if you first rep flies up do another. If that one is easy do another. So you have three and you done. Decide, how much you want to put on the bar based on how hard THE WHOLE set was (so see..your looking at the effort of each rep individually to decide if there should be a next rep then your looking at the set as a whole to judge how much to put on the bar).
5. If a first rep is harder than you feel it should be then your done. Rest and go for another rep at that same weight and see if you do better and then follow the same procedure to go forward as above. If the first rep is fine but the second rep makes you feel like a third rep will be too tough to maintain good quality then your done at two reps.
SO WHEN I SAY QUALITY I MEAN EVERY REP IS DAMN GOOD. YOU DO NOT NEED TO GET NEAR YOUR MAX LIFT. YOU ARE JUST TRYING TO GATHER LOTS OF GOOD QUALITY VOLUME AT AN INTENSITY THAT IS MOSTLY GREATER THAN 85 PERCENT.
6. Any trick you need to do to acclimate better as you go along is fine. Say you've built up doing singles, doubles, triples, whatever happens unitl you have 385 on the bar. You do one rep of 385 and it's WAY tough. You might put on 10 more pounds and grind out a rep. Then rest a lot and drop back down to 385. For that "quality" is not going to be as good but you will only do that once or twice if you need to so it's no big deal.
7. You just keep doing that set after set until you know that you cannot get any more weight on the bar without sacrificing quality. For a reference to what I mean about quality look at your last set of 415. The quality was REALLY good for a set of 415x5 but not quite good enough for this. I.E. on some of the reps you back was rounding just to the edge of "safe" and things like that. So this quality volume should not be that far to the edge of your ability.
If you take your time and do this right you can end up with some serious weight on the bar. There are no rules as to how heavy you can or should go. Let quality be your guide. The 80 percent thing was just to get you started. After that don't worry about percentage at ALL. At the same time PLEASE do not have some abitrary number in your head that you want to reach.