I have only ever seen post sear and I agree with Sauron that I would only sear once.
The other thing is that after your sear there will be bleeding, you will lose a lot of moisture into the bag. i'm not sure if that is desired or not but in my mind you will get a grey messy soup round your steak.
The problem with this method is always going to be that it creates a moist environment which inhibits dry surfaces needed for proper deep searing. You can of course use method to help with post-cooking searing, but you're going to have to do it whether you utilise a pre-sear or not. As the Chefsteps video shows, a pre-sear actually helps with getting that post-cook deep sear.
Anova Wi-Fi - Pork chops 45 minutes at 60C for perfect juicy chops and 24 hours for a shank that you pull apart with 2 forks. Hamburger patties done to perfection. Food straight from the freezer? Just add 30 minutes and then some crème brulee to finish off the meal. Go to the playstore and download either the Anova or the Joule app and then you can get an idea of the possibilities. Lot of restaurants have steaks floating in a circulator set for rare and when you come and order they take the steak out and put it in second circulator set for the temperature of your desired steak, then a quick sear when it is done and you have perfect steak.
Be careful with fitting the units to cooler boxes or covering it with foil or cling wrap for long cooks - at high temps you get condensation on the pc board. The correct way is using 20 mm plastic balls to cut evaporation which will be my next purchase from the UK if I cant find something similar local
Lot of restaurants have steaks floating in a circulator set for rare and when you come and order they take the steak out and put it in second circulator set for the temperature of your desired steak, then a quick sear when it is done and you have perfect steak.
When you start adding people into the delivery chain it becomes overly expensive. I could for example use aramex to forward it as well but shipping becomes silly and makes it not worth it. (unless Scott ends up being very affordable). Black Friday specials last year were excellent but the shipping issue killed it.