nah, been making these for a few years - never had an issue.
Also bear in mind this is leather, so doesn't have grain to tear along. Also not cut by scissors, burnt and sealed.
I can see your point - but these are meant almost exclusively for tennis balls anyway.
were you throwing 4lb lumps of lead - even then I doubt there'd ever be an issue.
Thinking about it, it is actually rounded anyway, for some reason stepper motors working together, never really do sharp right angles.
Plus with the way the pouches go together, that part is rarely stresed.
Previously for mass numbers I usually make these out of double denim (two pieces of denim glued crosswise with pva).
Again never been an issue.
Dunno how that stuff will cut - have to try it I guess