Espresso grind - coarse of fine?

Partsguru Ed Harris, you recommend a coarser grind and not tamping the grounds much before making espresso. I tried it and wound up with excellent crema and a delicious espresso. I used the coarser grind and lighter tamping in the Starbucks Barista espressomaker. This advice is totally contrary to most instructions that advise using a very fine grind and several pounds of tamping pressure. I just realized by re-reading the advice, you were referring to making espresso using the crema disc, which allows for pre-infusing. But, I simulated the pre-infusing by pressing the on button briefly to let water infuse the grounds for a few seconds before brewing, and didn't use the crema disc. Nice.