Flight crews avail themselves of ACARS met reports all the time. In my experience, company dispatch provided timely and up-to-date information on SIGMETS as a matter of flight following, a legal and operational requirement in many states. Most crews would plot the SIGMET'd area on their planning charts then keep a wary eye using all available techniques including radar. That is not where the problem lies. The problem is in teaching how to use the radar "optimally". Likely, most pilots pick up the use of their radar through "osmosis", which does not filter misunderstandings and shortcomings in knowing one's equipment.
Thanks, PJ, but the smart use of wx radar starts with being aware that things are tricky and warrant extra vigilance. My point is that since the AF447 flight crew according to the BEA report did not ask for nor did they receive SIGMET updates by ACARS, they were disadvantaged in their awareness. And I agree with you that SIGMET and other weather related info is and should be regularly supplied through ACARS, certainly on long distance flights. This makes the BEA statement on the absence of such communication with AF447 even more significant.
Saturn V, where did you find the ops message on the weather (your post 3437)? Surely not AF447 related; I stand to be corrected, but I couldn't find that in the BEA report (as there is no mention of SIGMET 8 and 9 for ATLANTICO FIR)