Actually, we're doing the exact same thing here. This was the original query:

while @i <> 1

begin

declare @a table(a int)

set @rc = @i + 0.9

set rowcount @rc

insert into @a select id from sysobjects

set @i = @i + 0.1

end

So, there was only one floating point addition which made @i<>1 TRUE, but in the if statement @i<>1 is FALSE.