Wally,
A couple of people have already mentioned "meter variance" to you but I'll echo what they have said. You are basing dose increases and decreases on numbers that are probably virtually the same.
With a BG reading of 400, and a meter variance of up to 20%, that "400" can really be a number anywhere between 320 and 480. If your BG readings are within that range, then you are making a decision to up or down on the dose for no real reason. It is no wonder that you are not seeing any big changes, because you are adjusting when an adjustment is not indicated by the data. The recent "strategy"? It isn't working.
Again, if you are not testing at any point in between shots, you have no idea whether the dose is right, too high, or too low, but you are making an adjustment (mostly an increase) anyway. The chances of Costello improving at all are minimal using this strategy. He could be going below 100 every shot. Likewise, he could be going over 500 after every shot, no matter what his PS reading is. One is caused by too high a dose, and the other is also caused by too high a dose. You can't tell if the dose is too high. You also can't tell if the dose is too low, but you are reacting as if you know that it is by continually upping the dose without justifiable data. Every time you up the dose without a mid-cycle reading, you are putting Costello's health and his life at risk.
I'll say it as plainly as I can, Wally. No matter which vet you see, and no matter what that vet says, if he tells you that his way is better than "our way", he's mistaken. Unless he has a record of remissions that is higher than the rate of remission on this board, he's not helping you, or Costello, and all you are doing is wasting money, and making it harder on yourself and most importantly, on Costello. On the other hand, following FDMB advice costs you nothing, and has Costello's best interests as the primary focus. The only benefit you will get from tomorrow's vet visit is that if the blood tests show something beyond diabetes is causing Costello's numbers. That would be great to find out actually, because otherwise, he's just going to tell you to keep upping the insulin which will probably cause more harm than good.
As Sue said, unless you can maintain a spreadsheet, and follow the test-before-every-shot and at least once per day around nadir time, we can't help you, or Costello. If you can't do that, then you are putting Costello at risk, period
Sorry, tough love, but somebody had to say it.
Carl