Can an External Task determine a DCR's PT?

System

Has anyone tried to determine a DCR's presentation template via a workflow's external task? I've looked around DevNet for a little while and haven't really found anything that applies, but found some good info, nonetheless. I figure this has to be a fairly straight-forward and common problem, but here are the assumtions:

1. There are possibly many presentation templates per content type, as described in templating.cfg,
2. DCR's only have the standard TeamSite/Templating/DCR/Type extended attribute, let's say nothing else and retrofitting is not an option,
3. The workflow itself has no notion (i.e. job or task variables) that can be used to identify the appropriate presentation template.

Okay, so I might be asking for the impossible, but at least might be a brain teaser. Let me know if you've done this before and what you did to discover the appropriate presentation template.

Thanks,

Dave

Current Environment(s):
(1) TS 6.1 SP2 on W2K3
(2) TS 6.1 SP2 on W2K