The whole "prove your thinking work" thing depends entirely on who's signing your pay cheque. If you're the only marketing person in the building, you're basically the junk drawer for every half-brained task that falls through the cracks. Been there. Planning doesn't exist because you're constantly drowning.
What cracked it for me was shoving everything into buckets. Social awareness, paid campaigns, media capture, client events - whatever. Under each bucket I listed every tedious bastard task that had to happen to get that deliverable out the door. Client events, for example: coordination meetings, invitations, press release, media alert, equipment, agenda. All of it. It became a visual nightmare that actually showed how much work went into one shiny output.
Once I had that mess on paper, I could roughly prioritise based on what the company actually needed. Took it to my boss as a visual aid. I'd already flagged a few buckets that could be shovelled onto someone else - or an intern. Frees up headspace for actual thinking work on the top three to five buckets. Half the stuff I offloaded was stuff other departments had just dumped on marketing because "we've always done it." Easy sell.
Started with a summer intern, then got an assistant, now we're a team of four. Still lean for the output we push. The difference? Higher-ups may not get what we do, but they know it makes money. If you're dealing with a boss who just wants to squeeze blood out of a turnip? You'll never have that honest conversation. They're cheap and they don't get it. Not your fault - just your shitty reality.