You make some very informed points. I think the point of their name doesn't really suggest they think we could 'Just Stop' however, Rather, it expresses the exaggeration at the endless foot dragging by governments in hock to fossil fuel lobbies or driven by short term electoral calculation. The direct action they take reinforces this exasperation: it's designed to cause a spectacle, to get up people's noses.
I think Labour's national plan for a Green New Deal is vital and long overdue. Your point about manpower is valid, and that is exactly the sort of thing such a plan would address from the off. it's another demonstration that you need the state in the modern world to take on large-scale risk and infrastructural planning, that neoliberal economics needs to just get the f**k out of the way.
I think they've got their naming all wrong, people who don't look into it (which will be most) will think they just want to stop oil now, it's a terrible marketing message. It's probably having the opposite effect as intended, by just riling up people who would otherwise want to do good (who are currently struggling).
Also the damage they're doing isn't a good look either, why cause the damage with the paint etc, or hold people up? All this is doing is adding on cost to the UK and the people, at the worst time possible. Ok, if you want to protest, do it by the side of the road or outside parliament, safely, in a peaceful way, but don't force that message on people who have zero control who are trying to make ends meet.
I know they mean "just stop new oil licences", but that doesn't make any sense either in the UK, we've got no oil, maybe that's why they're looking for it? The people who do have the oil are crazy, and the ones we buy off use slaves to get it. Do they want us to just keep buying from the slavers? We have to buy it from somewhere, the bigger problem is the demand for it we're still creating, it's baking that in.
Protest the companies using the most oil, or those selling products which will require the most use of oil (and gas).
The UK could be far more cost and time efficient on energy projects if we significantly reduced the ludicrous red tape and hoop jumping. We're at the stage now where it's so bad that it seems like 3rd parties are inventing things to try and stop things being progressed, as it justifies why they have a job. They're very slow to release information too, rather than just giving you what you want at an early stage, they just drip-feed it through. It's been like this for about 15 years and gets worse every year. It's not about wanting to be unsafe either (my company has never had a reportable accident of any kind in 15 years or whatever), everyone in construction (at least firms over 10 employees) wants to do things safely, they have to keep accreditations and win contracts. They know how to be safe (and realistic), just let them crack on and get done what they need to get done. Needing 6-12 months of reports and slow e-mail responses to put a pipe/ cable under or across a motorway, river or rail line does not need to happen, companies have known how to do this properly and safely for decades. Legals are a pain too, the time it takes for landowners to let people put infrastructure through farming fields is absolutely ludicrous, as are the costs.