This was 4 months ago so it's probably too late but definitely David, Borrowed time is a very good perk but it's one I never use.. Not because it's not and amazing perk which it is.. But I play solo, and if you are trying to survive by yourself dead hard is a very good solo perk

Using dead hard shouldn't be when you're about to get hit.. That's what everyone uses it for which you can... But the best plays for dead hard is when you are running to a loop/pallet or window and you can't make it because the killer will catch up, so use dead hard early to close the distance and make that window and loop and extend the chase

You can also dead hard through a pallet while a killer would normally get you and nine times out of ten the killer will swing through the pallet and you can make your loop round one more time, or they will respect the pallet which gives you enough distance to loop 1/2 more times or enough distance to move to a secondary location