Yes, nice to see that they're looking at Meadowhead and the Northern General, both would benefit from being on the tram (one line perhaps!) Slightly surprised tram/tram train to Dore isn't mentioned specifically but then I guess with HS2 as well there may not really be room for it down the MML corridoor. There may be room to extend a Northern stopper through Sheffield to Dore however and turn it there (easily do-able with two platforms I'd have thought) and would free up a platform at Midland - this would increase connectivity and give Dore a second train per hour to Sheffield.
I’m not even sure they were that behind it when the City Region Mayor was just on Calendar. Basically saying ‘we needed to create a list, so have created a list’
One of the things any feasibility study into the second Sheffield to Huddersfield service will have to consider is the cost and location of an additional loop (which will be outside the Sheffield City Region, by the way). If you were to be running longer-distance services in addition (presumably semi-fast between HUD and PNS) then realistically you'd need to redouble the whole line. As the single line has been realigned for speed improvements and better clearances in places, this wouldn't be an easy job.
Feel free to create a thread in Speculative Ideas to discuss this
The Penistone line is mostly single track with the exception of Stocksmoor Jn - Clayton West Jn (encompassing Stocksmoor and Shepley) and the passing loop at Penistone.
Large parts are. From Springwood Junction (the other side of the tunnel from Huddersfield station) to Stocksmoor is single, with the stretch into HUD platform 2 also usually treated as an extension of that single line. The double track then runs a few miles from Stocksmoor station through Shepley as far as Clayton West junction. Single from there to Penistone where there's a loop in the station only, then up to a point about half a mile from Barnsley station junction where it meets the line from Wakefield Kirkgate.