Yes, thanks for the warning. I intend to tiptoe with extreme caution here. I am well-versed in the use of a bullet puller and have no qualms about crying ‘enough’ before getting to the max load. I will be using Winchester WLP primers (suitable for both standard and Magnum loads) with WW-296.
Here is the latest data I found, from the June 2015 issue of Handloader magazine, where the feature article is load development for the 357/44 Bain & Davis in the T/C Encore. As you so aptly point out, they can withstand far greater pressures than a mid-century revolver, so I would be reticent about them for my Model 27 application, at least without thoroughly testing loads far below these.