I think there are two sources for this problem.
One is that user only send one request, LiteSpeed tries it multiple times due to back-end (PHP or backend app server) failure, like the charging credit card problem Tony had, for this part, it can be improved from LSWS internal.
Another one is that user get an blank page most likely due to script problem, each request only being processed once by LiteSpeed. User refresh the browser again and again. This kind of problem cannot be address by LSWS internally.