That won’t work reliably, and if it does work, there is no guarantee of success.
You need to pipe directly as you cannot reliably read from the SD card when you are performing block level write operations.
I made a slight typo in my command above, the correct command is:
wget http://download.osmc.tv/installers/diskimages/OSMC_TGT_rbp2_20160910.img.gz -O- | gunzip -c | sudo dd of=/dev/mmcblk0 bs=1M conv=fdatasync