The burned portion of food on the bottom of your Presto is not due to any fault of your GE range's "controllability," but rather to the construction of your Presto because you said it does not happen if you bring the pressure up on 2 or Medium Hi. Thicker foods might have to be brought up to pressure on lower heat to avoid scorching, but stainless steel pressure cookers with a thicker base with aluminum encapsulated in the base can spread the heat better and reduce the burned on spots. I had two Presto stainless steel cookers, the one from the 60s with the carbon steel core and the very curvy or rippled base and the design introduced in the late 70s which was just as bad at scorching food, and not just thick foods, when the pressure was brought up on High. The cookers made by Kuhn Rikon and WMF, because of their better bases, do not have the problem that the Presto has. Also, their bases remain flat at cooking pressure which is not the case with the lighter-weight cookers so a lower cooking heat can be used to maintain the cooking pressure since more of the cooker's base is in contact with the surface unit.
As to the hold over heat of the Radiantubes, I learned to switch the heat to the lower setting at the first sign that something was coming to a boil or before the pressure was reached and then I set the timer for maybe 3 to 5 minutes less than the cooking time called for so that I switched off the unit when the timer signaled and used the retained heat of the unit to finish the cooking operation. All of my older electric range manuals and cooking guidelines emphasize the economy of cooking with the stored heat and that has been the way I have approached electric cooking on any brand of range except for the induction units. As Mikael says, the things you usually cook, you learn how long they will need to come up to cooking heat and you quickly learn with electric cooking not to leave ANYTHING unattended over High heat. [this post was last edited: 2/1/2015-18:35]
