Has someone used the Mortensen method for HP5+ @1600?

How does grain look? Of course I bet sharp, but how obtrusive?
I don't have HP5+ in 35mm right now, and I found I got only one 120 left, so I won't use it for testing: I'll wait and use it for real photographs, doing the method with it soon...
Ilford's site talks about the method: a semi-stand use of ID-11 1+3, with 50 minutes of stillness in the center of the process, between 10 minutes of inversions every 30 seconds, and 10 minutes of final inversions every minute. 30 seconds of continuous inversions in the beginning...
It seems HP5+ can reach 1600 decently in MQ standard developers that way.
Very little info around... A couple of comments by pentaxuser in recent years, but I found nothing else.
Apart from being a great film, HP5+ is the only ISO400 MF B&W film we can buy inside this country (and ID-11 too), so this method may matter to me very soon. I use Microphen for HP5+ at 1600, but even if it does a better job than ID-11 for a two-stop push, its glacial tone, present grain and detail loss, make it a good option for some types of images, but not for everything...
If the method works, and the film -which is really great at 800 for soft light in ID-11- can be taken to 1600 with good tone and grain, I will use it for fast MF photography...
Any users?
Thanks.

It's maybe a pity that he does not compare a print from the Rodinal method compared the print from the Mortensen. Overall as far as the model's face is concerned the Mortensen semi stand method just shades it for me. Sanderson the author of the article says that Rodinal wasn't the sharpest either despite the general consensus that it should be but I wasn't able to see this on shots of the reversed negatives compared to the reversed negs from ID11 stock or the Mortensen negatives

pentaxuser

I've been using HP5+ for years with various developers and various developing techniques. Shooting the film at 1600 gave me underexposed negatives (IMO) no matter what developer or technique I used. In the end narrowed down to shooting it at 320 and processing it either in Rodinal with a 9% Sodium Sulfite solution or Tetenal Ultrafin. Just gave me the negatives that were a pleasure to print. Side note: I like "full density" negatives to print from. If I needed to shoot a film at 1,000 or more, I just turned to using P3200.

Oh, sure... I didn't mean 1600 as real speed: it'll be a push no doubt... What's interesting is the possibility of making that push look like a one stop push in a standard developer: that would be great.

The whole Mortensen idea is basically to take a very flat scene & expand it to 7 stops(ish) via gamma infinity development in a pretty dilute developer. It's important to note that the method proposed by Andrew Sanderson uses a less dilute (yet better buffered) developer than most of what Mortensen was using. It's also worth noting that a good 'expansion' development doesn't necessarily need to go to as high a contrast index as you might assume. I've expanded 4x5 HP5+ in stock ID-11 just fine - the main thing is to consider where you want to put your shadows.

Hi Lachlan, the other day I read some of your deepest posts here, related to lots of subjects, and I was really impressed... You are a true expert in photography, and your explanations are outstanding. Thanks a lot for sharing so much knowledge!
I don't know if experts like you would consider an expansion what I want to do: basically I want to be able to try my 35mm Summaron at f/11 (that aperture always in the street) inside my personal system (instead of f/8 at 640), so I wonder if HP5+, a film that's truly fast by nature, can give me a nice EI1250 for normal overcast, which isn't too flat... EI1250 is a bit less than what Mortensen and Sanderson comment as possible... The 35mm at f/11 generates depth of field enough as to totally cover field curvature, and the scenes often look great at that aperture, both because of DOF and sharpness across the frame, reaching good definition in the corners... I get great tone withTMY-2 in FX-39 at EI1250, and beautiful sharp grain, by the way, but I can't buy those two around here, and getting film and chemicals by international mail has become difficult and risky (veiled film: scanning and hand inspection when materials arrive to Bogotá) when not impossible... A good EI1250 with HP5+ and ID-11 seem a good option in my case.
As you said -and Mortensen and Sanderson comment the same- ID-11 stock does a great job at that too, so that's a good option as well: honestly I have never pushed HP5+ with ID-11 stock, only with Microphen, and it was recently that I discovered, comparing the same scene in both developers, how different image structure is in both cases... Detail is just a different story with ID-11, and Microphen implies a big loss in that regard even if films are generously exposed without any underexposure at all... Microphen makes sense for wild pushing, no more, IMO.
As always is for all of us, in this game we have to pay to see: I'll check 1+3 and stock.
Thanks for caring!