Nasty, Nasty stuff. Have a Sage 9wt Spey that likes to pull this trick on me in sections two to three on a 4 piece rod. Put out a "plee!!!" with the folks on the International spey casting board on how to seperate the darn sections. Contest :>)
Winner, and repeated several times since, is to take a section of aluminium foil and fill it with ice cubes. Get the connections/sections very cold and VOLA each and every time the da... things seperate.
Wax the connections? Bees wax, no scent, 'designer' candles because they have a bit of oil for the 'sniff.' Do wax the connections but go for the pure wax. But ... sometimes the best of plans .... and the foil and ice cubes have worked 10% of the time. No crank info, God knows why it works but it has worked every time.