Most of you will know who Mike Wesley is - no body knows the EEC better I'd venture to say - here is a quote from Mike's article "EEC vs EEC".........
Another thing the '94 - '95 cars do with spark is retarding it during a shift. The automatic cars REALLY pull out the timing, but the 5spd cars do it also. Inside the 5spd EEC calibration is a thing called Tip-in Retard. Any time the throttle is moved from a more closed position to a more open position, it can pull out some timing. When you shift a 5spd car, most people lift off the gas during the shift. The EEC senses this, and when you push on the gas again it pulls some timing out. The older EEC didn't have this 'feature'. You lose more torque during a shift on a '94 - '95 car than a '93 or older car. Why did Ford do this?? We think warranty. Ford had to replace a zillion T-5's in the older cars. A lot of them broke due to overshifting and power shifting, but a lot of them broke as a result of too much transient torque. If you could reduce the torque output of the engine during a shift, the transient torque would be lower. The trans wouldn't break as easily, and thus the Tip-in Retard was born. How much timing is pulled out during a shift varies, but it can pull out as much as 15 degrees. There is not much you can do to 'fix' this except by re-calibrating the EEC.
The '94 - '95 automatic cars have a torque modulation strategy installed in them to vary spark during shifts. When the EEC thinks it's time to change gears, it can pull out massive amounts of timing so the shift is nice and smooth. As far as we know there are two reasons for this. First is warranty. The AODE trans is not all that strong in stock form. By reducing the torque during shifts, you can extend its life. Second is shift feel. For some reason Ford doesn't want you to 'feel' the car shift.