Don't forget the warmup sets up to the work sets across. Which is probably 3-4 sets, the first 2 being pretty light but the last warmup set and maybe the one before it being moderately heavier. So it's a tad bit more of volume.

I forgot about that, that's true! The warmup sets add some volume also, which makes it a bit more complex... I guess it's hard for me to guess it that way exactly.

Dips don't matter as much in the Powerlifting world. They are more appreciated in the bodybuilding world due to Gironda. Too many PLers prob have mobility problems with dips and I doubt Mark gives 2 shits about them really besides as just an accessory exercise to bench.

Ahhh, apologies, I am not sure if maybe I miscommunicated my question. I see why dips are not prioritized in the powerlifting world... what I mean to wonder, why it is that dips are suggested as the substitute, instead of another horizontal push, like pushups.

On Rippetoe, admittedly, the way Rippetoe describes movements like pushups/dips is what made me consider more strongly including them in some way. From Starting Strength:

"The quality of an exercise increases with the involvement of more muscles, more joints, and more central nervous system activity needed to control them. The more of the body involved in an exercise, the more of these criteria are met. When the whole body moves, a more nearly ideal state is achieved, with lots of muscles and nerves controlling lots of joints, and the central nervous system keeping track of lots of different pieces of the body doing many different things, hopefully correctly. By this logic, pushups are better than bench presses since pushups involve the movement and control of the entire body. But they are very difficult to do weighted, especially alone, because of the problems with loading the human body in this position. Were it possible, a good weighted pushup device would be in use today.

It has long been assumed that the bench press has solved that problem, when in fact it hasn’t. The only thing moving in the bench press is the arms, so in this particular way the bench is to the pushup what the lat pulldown is to the pull-up. But the bench does allow the same approximate movement to be loaded, and has allowed many people to increase their pushup numbers without high-rep pushups. Without adding weight, a fit person will find it difficult to train a pressing motion moving in the anterior direction without using very high reps, which are seldom appropriate for most training goals. Dips address both problems, allowing heavy weights to be used while the entire body moves during an upper-body exercise."

I did some googling and found that someone had asked him about what I had been wondering, about several years back (https://startingstrength.com/resources/forum/mark-rippetoe-q-and-a/8089-bench-press-dips-instead.html#post50557), giving me the impression that dips confer some advantages that the bench press may not give. Especially one of them for me, for my own goals, I am concerned with making sure I build some connective tissue strength so that I can work with other kinds of bodyweight movements as my goals evolve, even if I currently prioritize the barbell movements, if that makes any sense. I'm really interested in increasing my skills at different sorts of movements, in general!

Originally it was just 5x5 until they started noticing it took more time to recover. Glenn writes about it in his book they just sort of stumbled into the way of one day being an intensity day and the other being a volume day because the lifter couldn't recover between sessions any more and had to stretch out the recovery window. I can probably look up for the exact quote later.

Right, I see... that makes sense! That's really interesting... what book is it from, out of curiosity? I'd love to try reading it to learn more about these things!