The recent posts come at a good time for me, as I'm getting to the end of my current supply of food, and have been full of indecision about what to do next.
I'm definitely going back to attempting rapid weight loss, that's not the thing I'm struggling with, and I'm planning on the ~800 calories a day idea, as I know I've been okay with that briefly in the past.
When I did a 'shakes' diet for about a week, some time ago now, I did on one occasion to a 2-hour reading and, in spite of having had 24g carbs from the shake, the reading was in the non-diabetic range. This was several days into the diet. Contrast that with times when all it takes is 6g to get a horrible rise. This suggests that even quite 'carby' shakes can be tolerated quite well a few days in; by me at that time, anyway. Probably helped by the lack of fat in the liver, as suggested. RT certainly says not to worry about the sugar in such shakes as 'after a day' on very low calories the body 'tolerates it quite well'. No idea what science he's referring to, but anyway my experience does coincide with that after a few days.
One reason for me to choose the shakes is that I bought a lot of them a while ago and they are all waiting to be used up! These sugary shakes (Tesco Ultraslim and the almost-identical ASDA version) are at least very easy to get hold of and very affordable. They may be artificial, but it's only for a few weeks, and I like that they are crammed with vitamins, minerals & macros that are deemed to be ideal for sustaining human life on low calories (albeit not people with diabetes!). It does take a lot of the thought out of diet planning, which I think gets more difficult the lower the calories in terms of making sure you get a good balance of nutrients.
The 200 cal of veg compensates any unnatural 'vibe' from the shakes - it's really a huge amount of veg and I used a wide variety last time, so felt I was at least packing myself with a greater quantity of something healthy than I usually do!
I think it was member CherryAA (sorry if I got the name wrong) who made the good point recently, that even if you're getting 75g carbs a day from these shakes (and I estimate another 20-30g from the veg), you're body is still on a relatively high fat diet in terms of the fuels it's using, because most of it is coming from your stomach (well it is in my case anyway!).
I think my dilemma is going to be resolved by committing to the shakes approach until they are used up, monitoring fbgs and the occasional 2hr postprandial, then the scientist in me will not be able to resist switching to 800 cals from LCHF real food for a while and see if I notice any difference!
Once I can't comfortably lose any more fat, LCHF, or at least eating-to-my-meter carb wise, is very much my long view.