> It is well known that there are some small peptides that are absorbed following oral administration. ...BPC-157 itself is said to be among this class

Do you know of any studies that suggest BPC-157 absorption from gut?

https://onlinelibrary.wiley.com/doi/abs/10.1002/jor.21107

Among others. If you read the paper, it's actually apparent that there's little difference between i.p. and oral administration in terms of efficacy -- both were roughly equally effective in improving MCL ligament healing.

Admittedly the paper's in rats -- as are 99% of the others -- as there's no incentive for anybody to run human trials.