The TI series of calculators. I've put a lot of hours in writing TI-BASIC programs. The single most tedious part was either scrolling through the program, or switching between alpha and numeric input.

For those unfamiliar, the entire Latin alphabet is overlaid on the existing keys alphabetically, and to type any of them (For variable names or assembly programming), you had to first press the ALPHA key, then your desired letter. Alternatively, you could press 2ND, A-LOCK and type in any number of letters, before pressing ALPHA again for numeric input.

Why am I saying all this? I want to write a code golf like challenge where scoring is done with this tediousness in mind, like switching between numbers/punctuation and letters carrying an extra penalty.

My original idea is that the source code of the submission would be converted to hexadecimal, and the number of transitions between alphas and numerics would be the "score," with a lower score being better.

How can/should I better refine this scoring system, and what sort of challenge should accompany it?

The TI series of calculators. I've put a lot of hours in writing TI-BASIC programs. The single most tedious part was either scrolling through the program, or switching between alpha and numeric input.

For those unfamiliar, the entire Latin alphabet is overlaid on the existing keys alphabetically, and to type any of them (For variable names or assembly programming), you had to first press the ALPHA key, then your desired letter. Alternatively, you could press 2ND, A-LOCK and type in any number of letters, before pressing ALPHA again for numeric input.

Why am I saying all this? I want to write a code golf like challenge where scoring is done with this tediousness in mind, like switching between numbers/punctuation and letters carrying an extra penalty.

My original idea is that the source code of the submission would be converted to hexadecimal, and the number of transitions between alphas and numerics would be the "score," with a lower score being better.

How can/should I better refine this scoring system, and what sort of challenge should accompany it?

The Challenge

Implement a program or function, in the language of your choice, that takes a string of characters as input and outputs that string's "tediousness score."

How tediousness is scored:

1. The string is converted into its hexadecimal representation. This is Unicode for languages that don't specify, but for a language like, say, Jelly, the Jelly codepage is used.
   "The quick brown fox jumps, over the lazy dog's back." in Unicode == 0x54686520717569636b2062726f776e20666f78206a756d70732c206f76657220746865206c617a7920646f672773206261636b2e
2. Each switch between numbers and letters in the hexadecimal representation is counted.
   0x54686520717569636b2062726f776e20666f78206a...
..0 12 34 56 78 9...
3. This is your tediousness score. For this example, it is 25.

Standard loopholes apply.

Should I change the tediousness score? How might I implement golf? I thought about adding/multiplying the two together, but it still seemed to be in favor of just plain golfing. I wanted to make golfing languages be a bit harder for a golfing challenge, since they really pack their character sets and there would be a high "tediousness score".

Is the challenge, as written, clear enough? Should I restrict or relax the I/O requirements?