Do you water down low wines for the spirit run?

[rumbo]

I'm making rum through a pot still. If I do stripping runs of 4 x 20L washes, I will have approx 20L of low wines if I take it right down to 20%. I have a 50L boiler. Should I water the low wines down before doing a spirit run? This is often not made clear when being discussed. If it "opens" up some of the flavour compounds or acheives some other black magic, then I will do it. If it makes no difference then it seems like a waste of heat input to bring a larger volume up to boiling point. I'm using a gas burner so no worries about ensuring the element is covered etc.

Cheers.