It is possible if you can manage:

1. Discipline
2. Time management. Raid start at 6.00PM, online at 5.30PM
3. No drama, just bear in mind, this is just a game. Keep your problems elsewhere.
4. Judge people by skill over experience. You've played WOW for 100 years, but still you're the 1st one to die.
5. Good communication skills and great leader.
6. Set rules on loot. (To prevent loot whore)
7. Make sure you don't have people under 18 y/o in the guild.
8. Give 10 minutes break for every boss kills.
9. Dont cramp the Vent, make it organize.
10. Avoid chatting in trade or general.
11. Wow is a srz business. Treat it accordingly.

Last but not least and the most efficient part is, IF i have tons of money, I'll setup a house and put 25/10 people in it, and give them salary to raid with me. They will play according to office hours and have OT , if they tends to stay overnight. there will be KPI bonuses each year, according to their death, awareness and punctuality.

Like TS said, if IF if if the internet connection are not the reason, no matter what we using. I know we have terribad ISP, but still its play-able. I know, yellow/red can kill us or even frequent disconnection, but that was a risk we have to take to play online right. BTW, good stuff you got there