mattie i don't look at monthly charts because my trade windows don't require them...i look at three time frames for my trade windows, let me give an example; if i was looking for a bottom reversal, i typically look to downtrending dailies...if i find sumpin that looks like it may be exhausted, i look to confirm it with the weekly histo divergence...if it is diverged i drill immediately down to the hourly for signals there...if i buy the hourly and the trade pivots and continues, then i would have captured the pivot long before the monthly chart will show it....if the reversal does not continue, it usually ends where the down trending, upper trendline is, so it's either a forced scalp or a reversal...and in some cases, a fluke....utilizing three time frames is effective in all lengths of trade windows...
i am in full support of your "safe and sane" approach to monthly data, it's just a time frame i don't utilize....so the answer to your last quesstion would be weekly, as in exhaustion...
if i can expand on any of that let me know, don't know if it made sense to you, but i enjoyed the exchange...