I replaced some very old and very heavy fl. fixtures today in a residence. There were j-boxes installed adjacent to the fixtures in the ceiling (recessed fixtures). I ran new romex to the j-boxes and attached my new romex whip to the new fixture. My question is I know this is required when old romex is used due to the temp. ratings. How many of you guys do this when working with old bx? Standard practice or don't bother? Honestly now.