pirmin-cowell

The 2 hot ends are temperature regulated so they will always maintain the desired temperature, therefore having 2 next to each other shouldn't be any problem, the hot ends will probably just reduce the power output to maintain the set temperature as some of the heat lost by the hot ends would heat up the other hot end. The problem I believe is that the other parts above it shouldn't be hot, are heating up because there is inadequate insulation between the 2 areas and not enough cooling from the 3rd fan behind the heat sink to remove all the excess heat from the white connector and other components in that area. Without fixing these issues, the white connector, Bowden tubing and filament expand and deform causing filament jams.

If the next big announcement isn't the dual extrusion upgrade, then I will try out the Pryogel-XT blanket for myself, because if it does perform as well as advertised, and possibly added in conjunction with installing a small fan infront of the print head to reverse the airflow, than it would be a very cost effective solution. The blanket costs $30 for a 30cm x 30cm x 5mm square and can handle extreme temperatures

Nope, the Pyrogel-XT blanket is rated for industrial use up to 650°C/1200°F and I was thinking about the 5mm thick version.

If heat conduction is a problem, would using an aerogel insulation blanket directly above the heater block fix the problem, or would a solid plate of about ~5mm thickness be better? I found a cheap potential solution, Pyrogel-xt blanket , is it worth a shot to try it and DIY dual extrusion? http://www.buyaerogel.com/product/thermal-wrap-tw350/