Afaik manufacturers do not encourage splitting and reusing chain links. The links aren’t intended for multiple openings and closings and the snapping into position gets weaker. When pedalling the chain is in tension helping to pull the link shut, but offroad the chain is slack more often possibly enabling the link to open up unexpectedly.
I've never opened one up while riding, but I have snapped a couple SRAM "non reusable" links when opening them up to take off the chain. Shimano ones seem rock solid even after several uses though.
Afaik manufacturers do not encourage splitting and reusing chain links. The links aren’t intended for multiple openings and closings and the snapping into position gets weaker. When pedalling the chain is in tension helping to pull the link shut, but offroad the chain is slack more often possibly enabling the link to open up unexpectedly.
Is the manufacturer guidance overkill?