Some explanation of splay_time, Splay() or the former's computation from the latter would be welcome.
Splay() appears to compute a pseudo-random number between 0 and 1 (I'm making guesses about the hash function used); this is then multiplied by a number of seconds read from (IIUC) a config variable.  This might plausibly be an attempt to ensure different hosts, by using this as an offset on when to talk to a hub, avoid collisions; but I shouldn't be having to guess about this stuff !
Of course, if it's all documented as part of that config variable, a sufficient explanation is a reference to that documentation.