Defining height and width on images
I might be crazy....but I thought I read something a while ago which said that when coding for email, it was best to avoid hard-coding values for images (through width="" and height="" attributes). I thought this might have been for mobile or Outlook, but I'm not sure.
What's best practice here? I know I should be creating images at the actual size I want them displayed on desktop - so how will setting a hard-coded width and height affect my mobile rendering? Are there any benefits and drawbacks?