No don't need that! Doesn't sound good at all!
Once I had a Moto Guzzi Spada, tried draining the fork oil once, not much came out, but also because I could not get top caps off, which would have let the air in to get the oil to drain, so I assumed they were both empty and used an oiling can to inject fork oil back up into the drain holes. Next time I went out on it, it was like the forks were solid rods. :
:
Moral: there are no short-cuts ... top caps had to come off (aka do it properly)