When I first started airline flying, I had the good fortune to fly quite regularly with a very experienced captain.
He had also been an AEW pilot and, as you know, these aircraft carry a very powerful radar and large aerial.
His advice was always to have a good look at the radar picture to confirm where the "weather " was. He would then take up clearing headings,(with permission of ATC) switch the radar off for a while and then check the situation again after a few minutes.
Never failed !
The theory was that, as the lightning will take the shortest path, it will follow the return signal of the nearest radar - in this case, us.
Always worked for me, apart from a couple of times, in over 25 years.
Just luck ?.....or anything in it.
Oh, and re: plasma balls (ionised gas) down the aisle, apparently a regular occurrence in 707s.
Sleeve.