I noticed an odd issue with some new templates we've rolled out concerning dynamic content. The issue stems only when making sections dynamic--the templates work flawlessly when content is static.
What appears to be happening is that when a section becomes dynamic, the inline styling of any elements within that section are ignored and substituted with the internal styling in the <head> section. The inline styling isn't erased from the actual code when you make the section dynamic, it's just ignored. Below are examples of what you see when an example is sent with static content, then what happens when it's dynamic. It's also worth noting this only occurs on a live send--sample emails, even of the segmented versions, show correct.
I've asked support but they aren't particularly helpful as it involves custom code (even though I believe this is an issue with rendering and not the code). Here's the full template code: [HTML] Marketo Email Template - Dynamic Content Issue - Pastebin.com