I ptefer to offer my sincere advice. I never pre-wash DMC. I never pre-wash Weeks Dye Works overdyes because both brands are colorfast. Weeks will label the 1% of theirs that aren't.
By industry definition, colorfast means that the color will not bleed onto other colors/fabrics if washed per manufacturers instructions. Both companies recommend cool water.
For other overdyes, I use lukewarm to very hot water, per recommendations on label or on their website. As far as tangles, it is impossible to wash, rinse, blot, rinse, blot, rinse, blot, hang to dry if no color bleeds on blotting. As a masochist, I recently was awarded the job of pre-washing nearly 100 skeins of overdyes that needed hot water wash. My hubby strung a clothesline on the kitchen over sink and counter. I washed, rinsed a lot, blotted a lot, towelled gently, hung to dry. Despite using tongs, burnt my hand. Oops. Lots of tangles despite carefulness. Recarded all floss after untangling. Will have Weeks convert all other overdyes to their colors by email, as no complete conversion chart exists anywhere on the internet. My long answer your short question!
Short answer: always tangles.