I know this is unsolicited, but disregard it if you chose.
If you take DAT Bootcamp seriously, you can get above a 21 no problem.
What I mean by serious though, is that you need to be striving to get a 30 on every single practice test. Understand everything you got wrong on all practice tests / problems
What every. single. video.
Make flashcards for every single fact, every reaction (I made ~2000 flashcards)
For the bio, don't just memorize the answers...look at all the other options as well, if there's a word you don't know - new flashcard.
DAT Bootcamp has ~ 100 pages of condensed bio review. I made a flashcard for every fact (minus biotech, as that was my degree.
The only way to really get better at the PAT is to practice.
This is really all a time game. I made terrible scores on the practice tests at first (like below 14)...but was able to work it up to a 24.
Different strategies work for different people, but it is incredibly easy to spend too much time on the Keyhole section, as well as the Top Front End section. The trap is you can rush and do a crappy job, or you could spend all your time that you could have used for easier sections. What worked well for me was allowing myself 10 minutes for the Keyhole section, but not worrying about time for each individual problem...I just solved each problem (knowing that I got it right before moving to the next one). Once I saw 50 minutes left on the clock, I marked the rest of the keyhole problems and moved to the TFE sections...and repeated the same strategy.
With 40 minutes left on the clock, I marked the rest of the TFE problems and moved to the angle ranking. (There aren't really many tricks to these first two sections that I know besides what is mentioned on DAT Bootcamp)
From my perspective, you MUST practice the angle-ranking so that you can race through it. I practiced it until I could reliably get 12 / 15 correct within 5 minutes.
For the hole-punch section, you must race through it. Spend time practicing solving the problems using only your mind, as this will make you faster; however, also learn how to draw a grid and solve the problems this way. This allowed me to eventually get to 15 / 15 correct for this section in 7.5 minutes. To solve with the grid, simply draw a 4 x 4 grid. Add a dot anywhere there is a hole punch. When you're going for speed, you usually DON'T need to visualize HOW the paper got to it's final form...you just need to see the before and after, and see the plane in which the paper was folded...and draw the second dot equidistant from the plane to the first dot you drew. Repeat this process.
(Also, pro tip: you don't need to draw 15 grids...even though you aren't allowed to erase on the real test...you can start by filling in a grid with a dot...then use an " X " for the next problem....then fill in squares for the next problem...this way you only have to draw 5 grids)
For the cube-counting, practice doing it for a while without using paper...it will make you better. Then get used to drawing up a table. Each set of cubes will be the subject of 3 - 4 questions, so METHODICALLY, but quickly, count all the cubes of teach type and mark them in your table. If you practice this well, this is an easy 15 / 15. But don't underestimate it...it's super easy to make a careless mistake here that will mess you up.
For the pattern folding, here are a few things I checked that helped me.
For patterns with no coloration, first check if all the faces of object to be folded. Find the most irregular-looking one, and quickly try to find that one in the answer choices...often, only one of the answer choices will have that face exactly the same. That's the correct answer, don't second-guess yourself, you'll waste time.
If this doesn't solve it, look at which faces touch which others...sometimes all the answers will have the right faces, but they aren't touching each other correctly. (In other words, while not all contacts can be easily seen in the pattern to be folded....if you see two faces directly touching each other in the pattern...they will guaranteed still be touching each other in the final object).
Another thing, for the cubes...they can sometimes be tricky. What helped me was looking at an answer choice, picking the corner shown in that answer choice...and then finding that corner in the pattern given....if they are compatible, then it is your answer. Don't waste your time checking every single one. Also, think chirality for the corners...clockwise vs counter-clockwise orientation does matter.
If you weren't hung-up at any point, you now have time to go back and solve any hard problems you skipped or couldn't get to on the TFE or Keyhole sections.
My Best Bootcamp and real DAT scores were:
Bootcamp:
Bio - 25
GC - 30
OC - 30
PAT - 22
R - 25
QR - 22
Real:
Bio - 30
GC - 28
OC - 23
PAT - 24
R - 22
QR - 26
Honestly, the Reading and Organic Chem were easier on the real test than on Bootcamp, but if you get sick....just re-schedule the test.
The real test is easier, but if you take this for granted you are likely not to get a 21.
Just a couple mistakes quickly takes down your score, so you really need to practice on bootcamp like it's the real thing, and don't just aim for a 21 on Bootcamp...aim for a 30.
I studied for 12 weeks and didn't use anything other than Bootcamp (it's seriously worth every dime), but you really have to be disciplined about it. If you're not committed to it all day, then I strongly suggest starting far earlier if you want to study leisurely.