Spotlight and Dual Boot System (not bootcamp)

Please forgive me this will be long as it is difficult to describe. At home I boot my laptop off an external drive because I am not the system administrator of the MBP. That way I can install and alter things without causing my work IT guy grief and consternation . I saw on the WWW that before Leopard was released at least on person noted a bug that caused issues with Spotlight messing with the Spotlight index of a non-boot drive (that sometimes could be used as a boot drive).

Last night I installed Leo on my external boot drive, and was surprised to see that I could also install it on the internal drive of my laptop of which I am not the administrator. No big deal I know what I'm doing. As a precaution while using my external boot drive I made sure the the laptop's Macintosh HD was ignored using "Privacy" Today while booting of the laptop's HD I noted no Spotlight index. I wondered why it had not started to index the internal laptop HD, as the machine was not booted from that. I checked the Spotlight sys. prefs. and found that the laptop's HD had been designated as private. I don't recall ever doing that while booted in the laptop's HD. I only did that while booted on the external HD

Is there anyway my external HD Spotlight's system prefs. can effect my internal laptop's Spotlight System Prefs.? Wouldn't the indexing be specific to each boot drive (even if it included an index of another drive on the current system?