Someone should ask Corbyn, like a decent journalist for instance.
My personal opinion, fwiw, is that if you're genuinely serious about a 'new way of politics' then electoral reform to a proportional representation system of some description is a must.
There are some issues that can come from STV and so on, but I doubt it can be worse than FPTP and there's data from Northern Ireland to see how it pans out in the UK.
Has Labour said why they imposed a whip on this?
Why abstain? Could it be because they don't really want to change the status quo but don't want to be seen voting for the status quo?