An update on the MDT handle. So far, as it has always been below freezing when I shoot, I always have gloves on. I noticed that with the MDT handle I tended to grab the bolt to cycle it, even when I tried to use the palm of my hand I would find myself grabbing it with my fingers.
I pulled it off, and immediately saw about a 0.2 second drop in par times for this drill with the bare bolt, still in the cold, still wearing gloves. I have not put the MDT knob back on, and prefer not having it even when shooting slow in the prone.
Some of this is technique. I have trained specifically not to grab the bolt in the past.
Basically the thumb stays on the rifle stock,
The hand rotates up pivoting on the thumb and catching the bolt handle with the webbing between the thumb and palm,
The bolt handle stays there as the hand pulls it back,
Once the bolt hits the back stop the hand keeps traveling back until the bolt handle is in front of the palm
Then the palm is used to bring the bolt into battery and the downward stroke becomes part of the motion to place the trigger hand back on the stock
@Formidilosus may (with good reason I'm not aware of) call BS on the above. However, it is faster than grabbing the bolt, it relies on midsized muscle groups that maintain function better under duress, and the trigger hand is always physically in contact with the rifle, so at no point is the brain having to track both the rifle and the hands location (which becomes more difficult under stress). It also makes short stroking the bolt very unlikely.
The MDT bolt knob interfered with that, even after using it for 1000 or so rounds.
Edit: There are some inaccuracies in that description when it comes to a Tikka (I picked mine up to double check myself). The bolt handle is too far forward to naturally fall on the webbing, in fact when I pivot my hand up my fingers catch the handle close to the second knuckle of the pointer finger (this is probably why I always want to grab the bolt.
I don't have it to check, but I remember my Kimber being different, which is a good example of how changing platforms can have unexpected effects. I'm also now holding for a neutral thumb, and not wrapping the grip with my thumb, which places my hand further back on the stock.