that's standard POS
if you have 2 inputs that are weighty enough you will have twice as much likelihood of staking.
- which means if one stakes, then you still have an input that is ready to stake and should do so,

in a healthy staking network
when your large input is divided into 8 inputs, those 8 inputs should give you roughly the same return over the same time frame as 1 input.
obviously there will be differnt timing involved as all inputs will take random time to actually stake

edit.
after some consideration i'm thinking i'm not talking about the same thing.

because there wallet will end up staking once /45 days all the inputs will end up much smaller hence they will receive less compound interest due to their entire balance staking less often than possible.

i think i agree with you i dont know of their motivations though, so perhaps either they are fine with not raping the staking or they are running different code

the code in question is wallet specific and the blockchain couldnt care less about these values, so they may well be aware of the issues and running a different code.
it would be easy to set the split time for anything you want.

.
i think you make it fairly clear what you mean in the last post on that thread.