Wlodzimierz Holsztynski wrote (2004-02-01 14:00:24 PST):

Karpov avoided "succesfully" a championship match
against Fischer.

_
If Wlodzimierz Holsztynski wants to blame Karpov
for failing to agree to a requirement that he would
have to try to finish two or more points ahead of
Fischer, it seems to me that he should be explicit
about this instead of using vague language like,
"avoided 'successfully'".

"Bobby Fischer had sent in a number of demands ... Some
of these were conceded ... But two demands were rejected.
... Numerous telegrams had been sent to the Congress by
Fischer via his spokesman, Fred Cramer. The last one said
that, in the light of FIDE's decisions, he was resigning his
FIDE world-championship title. ... Another attempt was
made to bring the FIDE and Fischer into complete accord,
when Colonel Edmondson (U.S. Chess Federation) asked
for the summoning of an extraordinary meeting of the FIDE
Congress. There being a sufficient number of countries in
agreement, it duly assembled at Bergen-aan-Zee in the
Netherlands from 18 to 20 March, 1975. It was an
extraordinary congress in every sense of the word, and
eventually, after much heated discussion, one of Fischer's
demands was conceded: the match was to have a limitless
number of games. But Fischer's other demand - that a
draw be declared when the situation reached nine to nine
- was rejected by a majority of three. Fischer's words on
hearing this were, 'It's all over then.' No match took place.
Fischer ignored the request to say by 2 April whether or not
he would play, and Karpov became the new world champion"
- Golombek (1976)

"Many have rather cynically described [Fischer] as
engaging in 'gamesmanship.' It seems more likely
that the capture of the title led to an emotional
upset of serious proportions. His conditions for
the match with Karpov seem motivated more by inner
fantasies than anything else. Thus so far he has
not played a serious game of chess since he became
champion. There is the grave danger that he may
never play again." - Fine (1976)