Want to do some more, JT?
Always open to suggestions, good sir ...
The reality is, smaller aircraft are operated outside the parameters of the performance charts all the time, by necessity.
If the operation is on the conservative side, I can see it being argued without too much difficulty .. but not everyone has the background to do the sums and argue the toss.
If the operation is on the non-conservative side, things could get a little difficult after the event.
Others, such as Bell 206 class (FAR 27), have it in the performance section and merely give the advice to "avoid".
Given the effort that goes into developing a limiting dead man's curve, and the risks associated, needless operation within is a bit on the scary side if something goes bang ... (while noting Megan's extensive rotary background).