I'm new to using TFS 2015 ALM with the integrated source control. Previously I've used the ALM with a non Microsoft SCM product.
I am used to creating the ALM project which has no linkto SCM.
Now, when creating a new TFS project I am prompted to create a new source control project. I cannot figure out how to use an existing source control project. surely the ALM is not directly linked to an SCM project of the same name, there must be a way of configuring the SCM project used.
A TFS project will always be created with one Source Control repository. You're free to use it or not.
It is possible to create a Process Template that doesn't initialize a Source Control repository, but none of the default process templates are configured this way. I'd not recommend removing this option from the Process Template as it makes upgrades and migration harder.