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5 by 5 knight's tour string validator

The squares of a 5 by 5 chessboard are labelled with the letters A to Y in English reading order:

```txt
A B C D E
F G H I J
K L M N O
P Q R S T
U V W X Y
```

Determine whether a string is a knight's tour of this board.

## Input
- A string of 25 distinct letters from A to Y inclusive.

## Output
- An indication of whether this string represents a valid knight's tour on the 5 by 5 chessboard. This may be one of 2 distinct values, or any truthy or falsy value if your language supports that concept.
  - If using 2 distinct values, you may choose either of them to indicate a valid knight's tour. Specifically, it is permitted to use `false` or a specific falsy output to indicate valid and/or to use `true` or a specific truthy output to indicate invalid.
  - If using arbitrary truthy and falsy values, so you have more than 2 distinct values for your outputs, you must use truthy to indicate a valid knight's tour, not the other way around.
- The string is a valid knight's tour if each consecutive pair of letters is a knight's move apart on the 5 by 5 chessboard. That is, the pair of letters is one of:
  - Differing by 1 row and 2 columns.
  - Differing by 2 rows and 1 column.
- The first and last letters do not need to be a knight's move apart from each other (if all consecutive pairs are a knight's move apart, it is impossible for the first and last to be, since the board has an odd number of squares).

## Test cases
Test cases are in the format `input : output`, with the output being `true` for a valid tour and `false` otherwise.

```txt
MJCFQXODGPWTIBKVSHENYRULA : true
ALURYNEHSVKBITWPGDOXQFCJM : true
IBKVSHENYRULAMJCFQXODGPWT : false
URYNEHSVKBITWPGDOXQFCJMAL : false
LIBJPWNCFTVSHAOURGDMXQYKE : false
NFDGRYKEHQXPJCLWTIAOUSVMB : false
ROHKVDTILUCYNGPBXMJSEWAQF : false
HEWALSJXBKRODVFQNCYITMPGU : false
```

## Scoring
This is a [code golf challenge]. Your score is the number of bytes in your code. Lowest score for each language wins.

> Explanations are optional, but I'm more likely to upvote answers that have one.


[code golf challenge]: https://codegolf.codidact.com/categories/49/tags/4274 "The code-golf tag"