Integrate with Feeds progress on String Explode

Am using feeds tamper to import one product display with has relationship to Commerce products as its variants. The list of variants is in the format "SKU1;SKU2" and then Feeds Tamper Explode is used to select these for the product.

Right now the Progress bar stays in Importing / Initializing for long time, instead of offering further feedback on the operations Tamper does with the field being exploded.