Cannot register multiple partial views for model type

Description

Step to reproduce

1. Register 2 partial views for the same model type (see TemplateCoordinator in Alloy).

Expected: Both templates are registered.
Actual: Only the first template is registered.

//Returns 4 templates in Alloy on 10.10.4 (includes both PagePartial and PagePartialWide)
//Returns 3 templates in Alloy on 11.1.0 (PagePartialWide missing)
var r = ServiceLocator.Current.GetInstance<ITemplateRepository>();
var templates = r.List(typeof(SitePageData));