will not work. The import calls can not be executed at run time they are like pre-processor commands, like 'h' files in C.
With that said you can then conditionally call a template within that imported sub-template. There has been a question on the forum from Todd and I have had a similar conversation with Pat and the gang at Emulex recently.
Emulex have a good use case for conditional template calling. They have developed an RTF Purchase Order template that generates terms and conditions on the back of each page. They are now moving out of just using the PO for their domestic market and need it to work in an international arena. Translations aside, they just need a different set of terms and conditions for the international market version of the PO. They are already importing a T&Cs template - all they need to do is create a domestic and international T&C template within the sub-template. Their XML has a tag in it identifying what type of PO is being generated, so they can have something like:
This would handle 3 possible T&C templates in their sub-template.
Todd had a good comment, why are the 'call' statements not closed with an 'end call'. I did not have a good answer. Suffice to say, we handle it for you - a good if inconsistent, feature. If you want some example code, get it here.