Some questions on incandescent mods

I'm quite new to this category. So now, a few questions:

1. Why is it necessary to overdrive WA bulbs in custom setups (eg. a Mag85 at 10.8V or more driving a 1185 rated at 9.6V)?
2. For the Mag85, is the 1185 the only usable bulb in the setup? Say, if I use alkaline AAs (instead of NiMHs) and drive a 1166 (11.6V) at 13.5V or more is that possible, and why?
3. Using fivemega's MN bulb adapter, which WA bulbs should I use in the SF M3T and M4 setups? For the M3T, should I use a 1274 (7.2V) and for the M4, should I use the 1166 (11.6V)?
4. What are the risks of running these incandescent mods? How much heat-related damage will be incurred in the flashlight bodies, parts etc.?

Thanks and please advise.

1. Why is it necessary to overdrive WA bulbs in custom setups (eg. a Mag85 at 10.8V or more driving a 1185 rated at 9.6V)? Overdriving produce,s a brighter light from the bulb while shortening it's life

2. For the Mag85, is the 1185 the only usable bulb in the setup? Say, if I use alkaline AAs (instead of NiMHs) and drive a 1166 (11.6V) at 13.5V or more is that possible, and why? The 1185 is the only bulb used in a mag85, 1185 bulb is what makes it a mag85

3. Using fivemega's MN bulb adapter, which WA bulbs should I use in the SF M3T and M4 setups? For the M3T, should I use a 1274 (7.2V) and for the M4, should I use the 1166 (11.6V)? No idea

4. What are the risks of running these incandescent mods? How much heat-related damage will be incurred in the flashlight bodies, parts etc.? I don't think it hurts the metal body's and on the good mods the sockets, lens, reflectors and sometimes switches have all been changed out to handle the heat. Some people have had battery trouble (explosion), melting stock parts and instaflashing overdriven bulbs.