Example 1: People have been asking about how to increase their numbers in the overhead press and many people have replied to them to get more size/muscle mass on their delts and upper back. I also found an article in Startingstrongman where Kalle Beck mentions about doing high volume;
"The goal is to get bigger stronger shoulders and more muscularity so do high reps. Work on hitting some good working sets at 3×8,3×10, 3×12, etc after you get used to the higher volume throw in some fun stuff like 2×20 or something. What I love to do is pick a weight you know you can hit for 15 reps and do as many reps as possible for 3 sets. A common set for me would look like this.
Once I was able to do 20/15/10 on those three sets I would bump up the weight. Notice every good presser you can tell they are good pressers? Big delts, big traps, upper backs, etc. You need to build up your muscularity to become a good presser." - http://startingstrongman.com/2014/11/03/5-exercises-to-increase-your-overhead-press/
Example 2: There is also a Supertraining06 video where George Leeman mentions he focuses on doing more reps and volume if he is looking to get strong and then after that phase i think he mentions about peaking.
So to sum it all up, should you:
- focus on more volume and then/possibly peak for a lift?
- keep pounding exercises with a heavy weight and moderate volume and get some from the both worlds?
- Just do exercises with high intensity and low volume?
(Sorry if there is anything wrong with the text my english isn’t my language)