my mom would always do tarka on high heat so she could get it over and done with (i assume).
i do it on medium heat and it's not so bad until i dump it into the daal. then it really gets into my throat. i think it's just irritates some ppl more. the hood fan doesn't really work.
Add the round dried red chilli at the very end of tarka (off the heat) when every thing else is alreay done. The chilli doesnt need to be in the oil for long.
do the tarka bit at the table, just before eating. Take the hot oil and spices outside in the garden, fry them, then bring in ready to serve on to the daal HOT!