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I recognize PLL with a combination of “Blocks” and “Bars” A block is two or three connected pieces, like so:

A bar is a set of connected corners. I’ve put bars in red wherever possible. The term “bar” is taken from 2×2 PBL recognition, so a bar may or may not include the edge in between the corners. (If it does, it’s also a 1×3 block):

You can tell the permutation of a layer (and its parity) by comparing blocks and bars in most cases. I’ve included some lookahead information for square-1 permutation, but the recognition part applies equally to 4×4 PLL. Listed is which EP case each permutation goes to with a proper Vandenbergh solution, and then information on 1-look permutation if it applies.
The E/X/Q cases are difficult to recognize with this technique, so I’ve added some notes to the end of the page detailing how I recognize these cases.

Permutation Recognition Corner Permutation Resulting EP 1-look Permutation
No parity:
U + J = U J 1 J
Z + J = Z N/A
H + J = H N 1 N
A + J = U J 2 J
T + J = U J 4 J
Ga + J = U N J
Gb + J = U J N
J + J = Solved J or J J or J N or N J
R + J = U N/A
F + J = U N/A
Y + N = U J 5 J
V + N = U N/A
N + N = Solved N or J 6 J
E + N = Z N/A
Opp Edges + Solved = Opp N/A
Adj Edges + Solved = Adj N/A
O + Solved = O N/A
W + Solved = W N/A
Opp Corners + N = Opp N/A
Adj Corners + J = Adj N/A
K + J = Adj N/A
P + J = Opp or Adj N/A
B + J = Adj N/A
D + J = Opp N/A
C + J = W or O N/A
M + J = W N/A
S + N = Adj N/A
X + N = O N/A
Q + N = O N/A

Notes on E/X/Q:
These are definitely the hardest to distinguish. The trick is to look at two edges, and the corner between them, and apply the 3-color rule. If there are 3 colors, that means EP is correct, so you have an E-perm. If there are 2 colors, you have an X, and if there are 4 colors, you have a Q.