Sadly, I have heard that two of my Green Party colleagues, Sarah Cope and Claire Phipps, earlier today lost their High Court bid to bring a judicial review of a returning officer's decision to reject their application to stand as job-share MPs in Basingstoke in the 2015 general election. (A similar attempt by Independents at a job-share in Weston-Super-Mare was rejected by the returning officer there as well, on a related note.) Sarah is a single mother with two young children to look after and Claire has hypersomnia, causing her to sleep for 12 hours per day (most adults sleep for 7-8 hours per day) meaning neither of them can be full-time MPs in practice.
Parliament still needs substantially better representation of women and people with disabilities than it does at present, so job-sharing will be useful in moving forwards in this regard. I believe, however, that electoral reform will be a fundamentally more important step in achieving this and breaking up two-party dominance as well, because multi-member, proportionally represented (whether via party list or STV) constituencies by themselves can allow job-sharing MPs, if they are large enough. The first-past-the-post system itself is not only unfair in terms of representing voters, but is also indirectly discriminatory towards women, people from ethnic minority groups, people with disabilities etc. It also means that if the local MP is failing to listen to voters, is suddenly incapacitated, or has caring responsibilities, people have no alternative representative to come to about national issues or grievances, whereas they will do in a multi-member Single Transferable Vote constituency (as a few voters from the Republic of Ireland have stated online).