bafadam, I know it has been a while since this post. First, I am assuming you are talking stp when you say template (I have heard this and custom site definition used interchangably with much confusion)
Not sure how far you got on this. Couple thoughts on your issue. First of all, not sure if you have ever tried this, but once you create a site with a specified template, you can totally delete that template from the system with no ill effects to the site generated using it. So while the expectation is that there is some link back to that template.
The problem with the resyncing capability would be once you define that site using that template it may have drastically changed, web parts, doc libs, etc. So a resync could be a dangerous thing depending on how much your site(s) have evolved.
if you have since found a safe way to do this though...please share. I could definitely see cases where such a thing could be usefull.