The whole pupose of playing roundwounds is to get bright sound from strings and many bassist keep the longevity of bright rounds by washing hands before playing then wipping strings after. So why greasing it. I don't gig or practice but don't blisters as 2 hours if that a week keeps my finger tips resistant.
I read sonewhere that keeping hands dry and use a bit of talcum powder on finger tips may help keeping then blister free?
I find new flat wounds to be bright but as you experienced bassist now they lose brightness quick.
Back to nose grease, if you run out of stuff, eye up a greasy punter in crowd.....
Have you tried ear grease?