I'm going to give you several reference letters I've written. I want you to
analyse them and produce a reusable style guide that another writer — or an AI
assistant — could follow to draft a new letter that sounds like me.

Analyse only what is actually there. Do not invent conventions I don't use, and
don't smooth over inconsistencies — if I do something two different ways, say
so and tell me which is more common.

Produce the guide with these sections:

1. FIXED IDENTITY
   My name, credentials, title, department and institution exactly as they
   appear in my sign-off block. Flag any variation between letters.

2. LETTER TYPES
   Do these fall into distinct types (e.g. student vs resident, residency vs
   fellowship)? For each type: how I refer to the subject, how I describe the
   working relationship, which strengths I emphasise, and the salutation I use.

3. ARCHITECTURE
   The paragraph-by-paragraph skeleton. What goes in the opening, what the body
   paragraphs each do, how I close. Note any sentences I reproduce verbatim
   every time, such as confidentiality statements.

4. VOICE AND TONE
   Be specific and quote me. Cover:
   - How I evidence a claim — do I anchor praise to concrete examples, and how
     specific do those examples get?
   - CALIBRATION: list the exact phrases I use at each strength level, ordered
     weakest to strongest. This is the most useful part of the guide, so be
     thorough.
   - How I handle a weakness or reservation, if I do at all.
   - Whether I benchmark against level of training, and the phrasing I use.
   - Sentence length, register, spelling conventions, formatting habits.

5. COMPETENCY DOMAINS
   The recurring areas I actually write about, in rough order of how often.

6. RECURRING PHRASING
   Reusable building blocks, quoted verbatim and grouped by where they appear:
   openers, relationship framing, strength statements, closings, sign-off.

7. DRAFTING CHECKLIST
   A numbered list to verify a new letter against before signing it.

8. FILL-IN-THE-BLANK TEMPLATES
   One per letter type, with {{placeholders}} for what changes per applicant.

Then, separately from the guide, tell me three things you noticed about my
writing that I probably don't realise I do — including anything that weakens
the letters or introduces bias. Be blunt about this part.