vacuum performance on insert - Mailing list pgsql-performance

Hi, I'm curious -- does "vacuum analyze e.g. table1" improve
performance on "insert into table1 ...". I understand the vacuum
analyze helps out the query -- select, etc., but just not quite sure
on insert.

Specifically, I'm doing the following.

1, delete records ...
2, insert records ...

if I add "vacuum analyze" in-between this two steps, will it help on
the performance on the insert?
More importantly, If so, why?

Thanks,
Sean