yes if the problem is overwatering specifically and only, flushing is pointless, but if your plants have been overwatered because they've not taken up nutes because of overnute, then the case is different I've had this problem myself, (spots) recently, when I was trying to bring my PH down with phosphoric acid and probably went a bit too crazy with my nutes, and they appeared, a flush and nute cutback seemed to help and hey, that shouldnt really hurt unless your plants are literally drenched at the rootbase.


goodluck anyway,

peace,
Denial