World Selection
It matters in WvW.
Due to the megaserver system, anyone on the same continental megaserver (NA or EU) can play together. The only impact your server selection has is you can only fight for that server in World vs World pvp
I imagine it would be difficult for me to control two different accounts and allow the two characters to fight effectively side-by-side. Unless, of course, the characters took turns. Still, they might not be very effective.
As noted above, it doesn’t matter which server you choose within a data center, save fighting/playing in WvW.
Good luck.
With the auto attack built into guild wars 1 & 2, I just have the two characters from different accounts start fighting. I just use the 1-8 skills for support in their fighting. I did it in guild wars 1 to assist in getting through the gate in pre-searing. As long as I keep them fighting in auto combat it works. If one falls the other uses resurrect on the other. I have a 18th level character in pre-searing that helps the other account raise the levels of its characters. I am mostly a PvE player, because I like the storyline and most people are above me in combat. Does it effect PvP, or can two accounts on the same server fight along-side and/or fight against one another?
I think playing against yourself in PvP would count as match manipulation (maybe not). It’s no problem in PvE, since, as you note, you have to keep both alive against the environment.
Regardless, as long as both accounts are in the same region, PvP/PvE aren’t affected; it only matters for WvW.
@Inclupatus: sure, it’s difficult, but it can be done (and it’s easier for people familiar with the game, profs, etc.)
Ha! Well, I did state effective. I was and am aware one can ‘auto-attack’, but considering all the comments found on the forums about people just using 11111, I was thinking it isn’t all that effective (except, maybe, using L80s in lower zones).
I guess it all comes down to what one wants to achieve. If it is just gathering loot/mats for some extra work, I’m sure it would work just fine.
Good luck.