Last flew the F-4 in 1986 so my recall may be a tad rusty. ISTR that the roll stab aug was pretty much optional unless you wanted to use what was laughingly known as the autopilot (would've been better named as 'the unusual position generator'). When tanking or flying in close formation, turning the roll stab aug off was vital as leaving it engaged made it feel like the aircraft was fighting against you. Also have some vague recollection that you were supposed to turn it off during doggers.
Losing the yaw stab aug (happened to me once just after T/O from Wattisham) made the ac try to fly sideways but was nothing dramatic provided you kept the speed at or below 300kts.
Lost the pitch stab aug once at high speed (generator failure I think) and that was quite attention-grabbing, but again, it was liveable with once I got the speed down and the RAT out.
The only other time the stab augs would fail (ahem) on odd occasions is when the nav was having a go at flying the 2-sticker from the back seat. The idea being was that the navs would be in awe of our god-like handling skills in piloting such an uncontrollable beast. However, in reality, all that would happen was a grumpy voice from the boot saying something like, 'Very funny. Now turn the stab augs back on, you b*stard!'