As so often these days, if you want real political insight, go to Mumsnet. In a web chat there today, John McDonnell has offered extensive proof that – whatever you think of his politics and policies – he is an extremely professional and skilful political communicator.

Mumsnet, as Gordon Brown, Nick Clegg and countless others will remember, is about the toughest gig out there: you’re faced with a bombardment of questions ranging from traditional political analysis to deeply personal issues and of course humour, much of it biscuit-related. Striking the right tone is very, very hard.

These days, Mumsnet is even harder for politicians because an awful lot of users there are (quite reasonably) very angry with politicians over transgender issues. They feel (quite reasonably) that their worries and questions about the impact of “trans rights” laws and practices on the legal and social rights of women are being ignored by many people in power.

Labour has policies in this area that many women on Mumsnet find troubling, not least allowing “self-defined” women to stand on all-women shortlists (a policy that may not actually be lawful, but that’s a story for another day.) Some prominent Labour figures, especially Jeremy Corbyn surrogates, have also dismissed and insulted women raising these questions.

So McDonnell was undoubtedly taking a risk when he went to Mumsnet. And how did he do? Pretty well, actually. So well that I expect the whole thing will prompt a bit more speculative whispering about his long-term ambitions and talk about who is the “real” Labour leader.

On the gender issue, he was strikingly conciliatory and balanced. Here’s one answer:

One of the key elements that has come out of this discussion is that most people I have spoken to on the spectrum of views have emphasised that whatever policies are developed people must be safe and feel safe. That is what I'm hoping, that we can build a consensus around a policy that enables this to happen. All our policies on whatever subject must be impact assessed for their safety and in the Labour Party and elsewhere we have emphasised the need for this to be applied, particularly for women, because of the long history of abuse of women within our society, regrettably.

Here's another, to a woman worried that trans rights are being promoted at the expense of women’s rights:

Women's rights are not considered less important. I believe that all views must be taken into account and I am convinced that we can build consensus around this. That is my hope.

As someone who has followed this stuff fairly closely, those words and that thoughtful tone strike me as not just very positive but also quite significant. McDonnell, of course, is a properly important figure in the Labour machine: it takes a brave comrade to cross him. And his tone here is simply impossible to reconcile with the “wrong side of history” vitriol that some noisy Labour people direct at women they dismiss as “Terfs”.

And here’s the really interesting bit from McDonnell, building on that promise to consult women who worry about these issues:

I have met with some of the women from Women's Place and will be doing so again. I was also approached (by) a number of women party members from constituencies in the south east and I am meeting them in October.

That’s Women’s Place UK, the grassroots group run by women including several trade unionists, which organises public meetings about gender law. According to quite a few trans rights activists (including some who really should know better) WPUK is actually a far-Right hate group. That claim is nonsense, but that hasn’t stopped the angry online mob waging cyber war on WPUK and anyone even speaking to them: when Caroline Lucas of the Green Party suggested she was prepared to meet WPUK to discuss women’s concerns, she was immediately damned by the modern witch-hunters.

And yet here we have John McDonnell, shadow chancellor and field commander of the Corbynite armies, promising to listen to women’s concerns about gender reform and to meet with WPUK. The angry mob’s reaction to that will be fascinating, to say the least.

P.S. Just a thought, but isn’t it a bit odd that John McDonnell, the Shadow Chancellor, has been willing to discuss the gender issue with Mumsnet but Penny Mordaunt, the Cabinet minister for women and equalities hasn’t managed to do so yet?