Here is how the glitch works: when you enter the boss arena, 7 objects are created and their RAM addresses are stored (as words) starting on $FFFFA808. So $FFFFA808, $FFFFA80A, $FFFFA80C, etc.
The first two objects are the wood bars that hold the spikes; the other five are the spikes. They are moved by the background deformation routine for MGZ2 when the boss arena is activated.
Now, the list is set only when the objects are
created. If the object is destroyed, it will still be on the list. The deformation routine does not check if the object has been destroyed, and will happily move the deleted object around, or any other object that happens to be allocated on the same slot.
These objects are freed some time after defeating Eggman. This happens when word @ $FFFFEEC6 is set to nonzero, which sets byte @ $FFFFEED3 to zero, after which the objects delete themselves.
But this is mostly irrelevant. As far as I can tell, all of this is essentially on a timer. The only relevant actions is when to enter the arena, how to manipulate the slot used by the capsule, and how fast to break the capsule; everything else depends only on how fast you kill the boss.
So add RAM watches for the 7 words starting at $FFFFA808 (in hex). For each of those values, prepend 'FFFF' and add a RAM watch for the hex longword at the resulting location. You want any of these to be $8672A, the code pointer for the capsule, when it spawns.
Since everything is essentially on a timer, the only thing that I could really do to improve it is make Tails break the capsule faster;
here is a video with the capsule being destroyed on the first frame possible. As it turns out, by manipulating when I entered the arena, I needed only to hold right with Sonic to manipulate the capsule to a favorable slot.
So: same in-game time, tiny real time gains, compared to Evil_3D's version.
