9psi EB - your ac compressor should not have locked - ac systems have a high and a low pressure switch (on the I6 its located just before/is part of the TX valve, which is up near the firewall on the passenger side) maybe it was defective?
Yeah, quite possible, but it goes to prove that it can happen....
The compressor was fine for 3-5 mins then it would just slowly get tighter and tighter and lock up, causing the clutch to slip (the mag clutch on the comp) This only happened when stationary though.
It was getting that hot that you couldnt keep your hand on the condenser.
The local air-con man that we go to said its a common fault with thermo fans not working correctly - so it must happen on the odd occasion for him to pinpoint the issue immediately (i initially overlooked this and thought it was just my comp. on the way out)
Personally, if it were my car (well, it was) or a mates car, I would wire it up so both fans come on together. Also this protects against fan, or fusible link, or relay failure.
Ensure you run one fusible link per fan, 1.0mm fusible link, and around 10 -15 cm is sufficient. I originally had blade fuses for each fan, but these had a tendency to melt quite consistently. (they were initially 30A each, then I also tried 2x20A parallel per fan)
The fans on my car only ever come on when stopped in traffic, 50 + km/h and the cooling is sufficient without fans, but its entirely up to you.
Me personally, I like to do things once, and know its not going to fail or cause problems later on, but people can have their own opinions - its entirely up to you on how you want yours to run.
My fans come on between the O and R on the gauge (EBII)