I don't think lack of climbing domestiques is really an issue here. In theory, they could line-up a strong team supporting Talansky in the mountain. The problem is, that's only in theory and circumstances don't play into their favour.
- Dennis could be an asset in ToC form, but apparently, he is not.
- Danielson could be an asset, but he is way off form this year for some reason.
- Cardoso could be an asset, but it was decided for him to do Giro-Vuelta.
- Slagter would be a big asset if he is in March-April form and Acevedo proved to be good in TdS.
Hesjedal always seemed to be a team-player. I don't think he would have any trouble with accepting the situation.
But apparently, Garmin wanted to have a good team in all 3 GTs, not only in TdF. In hindsight, they would be better with Cardoso at TdF and Howes or King at Giro, but I think it's lack of form from Danielson that complicates things. To have a Danielson who could climb with 20 best riders in the mountain would be more than enough here.
I do think it went a bit wrong in the planning, though. I think the team would be better with:
Giro: Martin, Slagter, Howes
TdF: Talansky, Hesjedal (cobbles, he did great on them in 2010!), Cardoso, Acevedo
To have Danielson, Dennis and Morton in reasonable shape somewhere would probably has helped too.