Candidate experience gets discussed as if it were a programme. In specialist markets it is decided by four moments, all of them small, all of them cheap, and most of them missed because of memory rather than intent.
One: the opening line proves you read something
A specialist can tell within a sentence whether you know their field. Naming the actual thing they worked on, with the source, is the entire difference between a message that gets a reply and one that gets a mental note that you are not serious.
This is a memory problem, not an effort problem. Recruiters do read the profile. They just read forty of them and cannot recall which detail belonged to whom by the time they write.
Two: the timeline you gave is the timeline you keep
"I will come back to you Thursday" is a promise. Coming back on Thursday to say there is no news is not a failure, it is the thing that builds trust.
Most damage here is caused by silence during a slow client, not by the slow client itself.
Three: rejection is specific or it is worthless
"They went with someone with more direct experience in X" is useful. "They decided to go another way" tells the person nothing and teaches them not to bother next time.
In a small market, the people you reject this year are the people you place next year and the people who brief you the year after. The rejection conversation is a long-term investment that most desks treat as an administrative closure.
Four: what happens after the no
A single message three months later, referencing what they said they wanted and something that has actually changed, converts more often than anything at the top of the funnel. It is also the one nobody sends, because by then the context is gone.
Holi exists mostly because of this gap. It keeps what a person told you, keeps the source, and puts it back in front of you when something relevant moves. Not to automate the relationship, but to make sure the relationship is not lost to a busy fortnight.
The uncomfortable summary
Candidate experience on a specialist desk is almost entirely a function of what you can remember at the right moment. Process documents do not fix memory. Neither does trying harder.
Fix the recall problem and the four signals happen naturally, because the intention was always there.