This topic is relevant to my interests hahah. I do high frequency benching.
I have a couple of comments on different points you brought up in your proposed training style.
bench press and military press every day: my comment is that it is not optimal. Benching on odd days and military pressing on even days is much better, although still a bit much. If you want to up your strength on both lifts using high frequency style and want to do both lifts on a same day, then doing them thrice a week, like Monday, Wednesday and Friday is good enough frequency. I feel that the eccentric portion takes a toll on you and shoulders and pecs are easily wrecked from too high a frequency)
doing bench (or Military) only and no Military (or bench), everyday: I still think No, even if you leave some energy in the tank.
no chest isolation like flyes, machines: Definitely agreed, except that some very light flyes (not meant as training sets but as prehab/therapeutic purposes) makes the pec muscles feel better.
Going to 90% of max every session: I am not sure if you meant working in singles up to 90%, or if you want to include back off sets and implement some repping-out. If you meant to only go for singles every training session, which I tried for bench, the advantage is that you will be conditioned to lift heavy singles any day of the week, but the disadvantages are 1)over time, I found that my grinding window for bench reps became very limited. Eg. by doing heavy singles forever, it made my grinding window suck so much that let's say 290 pounds is very easy, but if I load the bar up to 300, then I will fail the lift in 1 second without having the ability to grind past the sticking point. 2) There is simply not enough volume. Bench is something that needs repetition sets
Further thoughts: So basically I'll share my history. Regrettably though, the following details encompass my high frequency bench experience; I don't do barbell military press with the same high frequency philosophy. So this background history is all about bench.
I found that I totally couldn't bench every day at anything close to 90% without developing shoulder and pec discomforts over time. I then changed to benching thrice a week, and did 3 sets of singles every session. All 3 singles were about 10-20 pounds below my daily max strength. It led to the problem I highlighted above (volume was too low, and one cannot really get away with just doing singles for bench, and grinding window problem). Right now I am having success with a new template of benchingï¼?I bench thrice a week, and still go to a heavy single every session, but one single is enough, I don't do anymore singles. Immediately after that heavy single, I do some backoff sets. Usually 2 sets of repping out. The back off sets could be 7 rep sets, 5 rep sets, or 3, just anything as long as I am repping something out. Of course on lethargic days, I just do higher reps with lighter weight as back off.
So in summary, what worked for me is thrice a week benching for enough recovery, work up to a heavy single, but mix in rep work in the form of back off sets. So I have covered various levels of intensity: the 90+% range is trained, the ability to grind is trained using lower intensity levels, and volume too. Some have a mindset that for high frequency training, rep work is not necessary, but I think it is, for above reasons plus 1 more fundamental reason: rep out sets allow for some solid hypertrophy window, and allows for more blood to flow into chest and shoulder muscles (therapeutic and not a bad thing?) and stresses the joints less.
Some of the above is broscience-y (based on my personal experience only). I have seen some online lifters do great with daily benching up to a daily max, and things like that, so the last thing on my mind is to discount other ways of doing this high frequency thing. But just thought I would share this, and while typing this, I do acknowledge that training is very individualised, and different styles work for different lifters. I hope my perspective gave a fresh angle for thought, if not useful.