does "load index" help for fulltext search?

(originally posted in database.myodbc by mistake)

I'm trying to speed up a fulltext search (MySQL 5.0.21, table has
670,000 records, about 900MBytes, machine has 1GB memory).

Fulltext search speed is quite variable -- sometimes really fast,
sometimes quite slow, so I'm trying to identify ways to make it more
consistent.


Most recently I tried "load index into cache testtable;". This
doesn't appear to have any significant impact on fulltext search speed
- some searches are a bit faster, some a bit slower. Should "load
index" improve mysql fulltext search performance? If so, any idea how
much?