I stalked a wood (mainly muntjac) both have a .270 as a few fallow, Simon used a fixed power scope, mine at the time was my Z6 2.4-15x56
The thermal spotter worked well picking out lots of muntjac in the brambles also the fallow. I would wind the scope right back and then out, move a bit L-R as that way I could see any close branches with the low mag. Clear path wind the mag up whack, we still chat about a fallow to this day as it took me 10 mins to find the path it was back to the 70's with the golden shot up a bit left a bit but I got it.
With respect that sort of practice you cant do on a range which has cropped up during this thread.