Ahnasha was far from confident in Fendros' plan, partially because of some legitimate hurdles they would need to overcome, and partially because she knew his proposed methods would take much longer. "Fendros, it isn't that easy. Sure, if I could easily fill a grand soul gem, I would do it in a heartbeat. But...well I know you don't know that much about enchanting, but a grand soul gem is a very valuable thing. Losing one of those would be like, I don't know. losing a suit of plate armor. It's a major resource and not something that someone just forgets about. Sure, we get plenty of soul gems down here, but I just don't think the enchanters are going to be okay with losing track of their most valuable assets." She argued. Although, she was not actually [i]completely[/i] confident that Fendros wasn't correct. They did have more grand soul gems than they could fill. 

"I'm lucky the enchanters have enough taboos with necromancy that they don't keep close track of the black soul gems we obtain, especially considering they trap grand souls as well..." She continued, immediately regretting her words. A black soul gem could technically be used in all the same capacity as a white soul gem. The difficulty in obtaining gems was not her primary concern with pursuing white souls instead of black souls. In an attempt to recover, she continued her argument quickly. "Look, the gems aren't even the biggest problem. How would we ever have both the manpower and opportunity to capture the soul of one of these beings? Most of them are rare, and even if you do find them, that is a very dangerous fight. Mammoths are always found with giants, usually multiple of them. Minotaurs don't even live in Skyrim, and the Falmer warlords in this cavern are always protected by a village worth of weaker Falmer. And I wouldn't even begin to know how to find a wraith or a xivilai. People are just much more common, much easier targets."