Just saw this. I posted a similar question on TLF earlier this year and didn't get much in the way responses.
I can comment from my own very limited experience. I applied it on a few small test patches that had a mix of clover and tttf
It successfully nailed ALL the visible clover leaves, and it left the grass OK (TTTF) - that much was very effective. Then a week or two later some clover leaves had come up, but less than there had been at the start - I'd say roughly 30% of what had been before.
So that's says repeat applications, at best.
To me, I WOULD be fine with that (going with the strategy of repeat applications to ding the clover while pushing the grass)
But my concern is yours - what's the effect of repeat applications of salt on the grass and the lawn. And how much is too much.
The grass did get a brown tinge temporarily (As they warned it would). To be clear it did NOT go all brown like it had been hit with glyphosate, we're just talking just Green with brown tinge
I asked TLF about the effects of salt and how much would be tolerable and I didn't get much of an answer. The papers I found seemed to be oriented towards grass growing near saltwater.
I think we could ask the company for any data/ Academic papers on tolerable Amounts of salt. They should have that and supply it. Of course we'd have to review it critically since the company is sending it, but it's be better than nothing
(take it with a pinch of salt?)