"By contrast there's almost no growth in the use of EV (extended validation) certificates, according to Helme."
Doesn't surprise me, they're a bloody con.
Windows 7 - ok, you've signed your code so I'll not bother annoying the user and let them get on with installing your app.
Windows 8+ - ok, you've signed your code, but oh wait...what's this...not with an EV certificate, so popup warnings here we come again. Want to get rid of them? Well, that'll cost you even more than before (despite the extra checks probably taking about 10 seconds), and you can forget about software-based signing too...oh no, now the key comes on a physical doodad, so you can only use it on one development machine at a time, oh and you can forget about remote desktopping into it, cos we'll disable it if you do that (thank god for vnc), etc, etc...