Interesting.
On HO rigs, the ASD relay and fuel pump relay are kept off until the ECU sees a valid CPS signal. Then they are turned on and the engine runs normally. The ASD relay runs the O2 sensor heaters, part of the ECU (but not all of it), the alternator field winding, the ignition coil, the fuel injectors, and a few other things. So when you jump the coil off the battery you're actually powering a lot of circuits, not just the coil.
My guess is one of two things has happened. One, the ASD relay has worn out - try swapping it with another one to check that. Two, your downstream O2 sensor wiring has come loose from the transmission tunnel and dropped onto the rear driveshaft, worn through, and shorted out. This will usually blow the blue (15 amp? 20 amp? can't remember) mini fuse somewhere near the middle of the PDC that powers... you guessed it... all that stuff I listed under ASD relay. Check that fuse (and any others you feel like checking, if you get bored) and if it's blown, check the O2 sensor wiring and repair as necessary to prevent it shorting out again.