I love using overlapping subnets.
It sometimes eases deployments and avoids weird NAT-scenarios.
Also overlapping subnets can solve IPv4 shortage.
It is possible to route between mikrotik routers only wasting one public IPv4 address per Router....
Are you saying that assigning 10.7.19.89/29 (the same IP address) to two different interfaces and having different hosts on these two interfaces in the same network is a perfectly valid
This is not what you did! You used two subnets and one is a subnet of the other.
I do that all the time. E.g. to have a small isolated subnet from a larger LAN.
Say your LAN is 192.168.1.0/24 and you want to isolate some hosts on 192.168.1.32/28, you
can configure these two networks on a MikroTik router (two interfaces) and enable proxy-arp
on the interface with the larger subnet, then the router will route between those two networks
and you can do anything usual in a router. (access lists, connection tracking, etc)
A Cisco will not allow this, you are right. But a MikroTik allows this configuration and it is useful.