XF 1.1 Split threads at 1000 posts truth or urban legend?


Well-known member
I used to be on a big board back in 2005-2009 the webmaster insisted all threads be split at 1000 posts

Since there alot of the forums i have been part of have one way or another sprung off from that big board

yet now i wonder is it needed to split threads off at 1000 in my case

membership is 2 members (its a private writing forum for myself and my co writer, no reg allowed)
we run on a moderately powerful VPS.

How large could i let threads run?