I'm not even sure I know any ISTPs! How to spot them? Lol.
I have two good friends who are ISTJs and the female is fairly traditional about using tried and true ways however, she's first in line for something new if she can see that something is an improvement on the old.
I agree. I like the tried and tested if it's been proven to work. If it's not broke, don't fix it. On the other hand, if someone comes up with a brilliant new idea that would be a good change, I'll support it. I don't like change for change's sake, but sometimes there needs to be innovation because the 'old ways' or the 'recently implemented but clearly useless ways' need an upheaval.
I find myself being like the other female ISTJs you described. I'm usually not stuck dealing exclusively with the "tried and true" way. If I see something better, I'd most certainly rather do that. I find that along the lines of ISTJ creativity, we're not innovators (like the Ns are) that come up with whole new systems, but I am a synthesizer in the sense that I can look at a whole bunch of different methods that have been used in the past and I can see certain features of merit in each one. Then, I take out the parts of the methods that I think went really well, and I put them together or rearrange them to produce something that is new and more efficient. A lot of people have called me creative, and perhaps that is true to a certain degree, but really, I just don't like to waste time.
I like your 'synthesizer' idea
On other topics: I've always hated sport. Loathed it. If you're not naturally talented at it the really sporty people will yell at you, plus it's boring and too much effort

Adrenaline can be fun, but for the most part I don't like it because I become panicky, irritated, angry and I can't think straight.
As for this business of ISTJs supposedly enjoying keeping track of our money and all that, it certainly doesn't apply to me. I save it, but once it's put away I don't like to think about it. I make sure I don't spend too much but I don't enjoy going over my bank statements. My ISFJ boyfriend loves to do that sort of thing though.
I've also seen descriptions which suggest that we're good at mathematics because we like detail. I wish that were the case, but it was always my worst subject.
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is definatly a good description of my ISTJ mom. she also does not like aderenaline, shes not big on supprises, likes to have things well planed out in advance, is incredibly reliable, hates any form of acounting!, likes to know the ending to movies before she watches them, believes in things like wearing clean underwear incase you get into an acident, thinks steak cant be eaten for breakfast and cereal cant be eaten for dinner because they just cant be, always has to know whats going on, and is constantly inspecting even the smallest detail NOTHING escapes her eye!
I agree with the first bit of what you say but I'd never want to know the end of a movie before I watched it! If someone told me I'd throw popcorn at them. As for wearing clean underwear, ummm... well, obviously. Eat steak for breakfast and cereal for dinner if you like but I can't see the appeal at all just because I'm not that hungry in the morning and I'm starving at night!