ubiquitin
“Although generally for �takanas Hashavim�we are meikel”
Agreed on the concept and in theory you are correct. However, allow me to elaborate, when it comes to ultra-sensitive issues as Ishus and Yichus. There is no definite p’sak or procedure and, cannot be, as the Geirus is entirely up to B�D, and these cases need guidance of Gedola Horaha, due to the gravity of the issue ruled as a case-by-case basis. see res. Divrei Chaim A�Hv vol 2 (ch. 36 at the end ). Gedolim have to make sure that the �heter� does not become abused as kind of a tool for all who just want to intermarry, it can only be used as a last resort, and that is up to the B�D to investigate and decide.
That is why in many cases, many will not permit it, as it became normal procedure and instead of being used as a �tekanos haShovin� it became a Tikon L�evaryon�.