Dman,
I have always used them as a matter of caution. On the OEM spring there is pressure, maybe slight. I installed Eibachs and it was just the few minutes to run the spring compressor on them. I have in the past used the "blast them off" method as described. I have done it and NOT been very happy when the upper spring perch flies across the garage! Since that experience I always use it. Obviously, both James and Todd have done this with no ill side effects. It is your choice.
Also note it is the center nut, not the three nuts that releases the spring, as James pointed out.
We all have had different experiences with the work we do. That is the beauty of so many people being involved and contributing, even though sometimes it may sound like we have opposite recommendations.
Maybe next time I will not use the spring compressor for the NSX!?!?!?!
Did you e-mail me privately on this for the procedure?? I received two e-mails over the last week asking about a write up on it. I did respond, and I guess I need to get it into the FAQ.
Good Luck,
LarryB