I’m trying to understand LeadConvert code, but have hit a brick wall with how the tpl files are used.
The /modules/Leads/view.convertlead.php file contains the following line…
$ev->setup($module, $focus, $this->medataDataFile, "modules/Leads/tpls/ConvertLead.tpl", false);
Editing ConvertLead.tpl, or even deleting it has no effect on the lead convert page; even after clearing cache and repairing etc.
However if change the reference to the file, for example by changing 
$ev->setup($module, $focus, $this->medataDataFile, "modules/Leads/tpls/ConvertLead.tpl", false);
to :
$ev->setup($module, $focus, $this->medataDataFile, "modules/Leads/tpls/**MYFILE.tpl"**, false);
does have an effect, and breaks some of the functionality
Why is this? It looks like the code in ConvertLead.tpl is not coming from the file modules/Leads/tpls/ConvertLead.tpl, but somewhere else? Yet I’ve searched everywhere and cant figure it out?