No, you are definitely correct. When I had my piceus, he did not fare very well if fed large mice, or more than one small adult mouse at a time. He would almost invariably regurgitate. I fed him one small adult mouse a week, and that seemed to do the trick.
The whipsnake seems to do be the same way, though it will eat two or more rat pups at a time if given the opportunity. I would almost say that I prefer those over the mice too, and the snakes don't complain.

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Roy Blodgett
Green Man Herpetoculture
royreptile@yahoo.com

1.1 Drymarchon corais
1.1 Pseustes sulphureus
1.1 Masticophis taeniatus taeniatus
0.0.1 Coluber mormon
1.1 Lampropeltis getula californiae (desert phase)
1.0 Boiga dendrophila dendrophila
2.3 Pogona vitticeps (snow and red/gold)
1.0 Iguana iguana

“All men lie enveloped in whale-lines. All are born with halters round their necks; but it is only when caught in the swift, sudden turn of death, that mortals realize the silent, subtle, ever-present perils of life.”- Herman Melville