Every rifle + load is different. My PH at Blaauwkrantz Safaris did the 25-yard check thing to me and I wounded and lost a bushbuck due in part to the un-needed scope changes (to 6" high at 100 yards). That and shooting off a corn sack full of sawdust instead of bags of sand. Took a Caldwell owl-ears front rest filled with plastic beads next trip.
What you do is take a 25-yard pre-shot target along with you to use at the scope check. Also you DO need to know where your rifle + load hits at 25-yards. I almost lost a warthog on my first safari at Mabelingwane because I didn't know to aim a bit high at close range.
I have 25-yard data to complement the rest of it out to 300 yards and...
Lts of myoads shoot 1/2" LOW at 25 yards despite being zero'd at 200yards in some cases, but mostly at 100 yards. Some are dead on at 25 yards and a few are 1/2" HIGH. The rule of thumb stinks!!
