Staff Experience... does it really matter?

I am looking to upgrade staffing, namely in my Tech Director and Commercial roles...while I understand experience for the Tech Director, I don't know what it does for me beneficially to have staff with more experience other than costing me more money... especially in the commercial and medical roles.

Is there Amy explanation as to what benefits I would get as a manager in hiring a Commerce director with say 12 experience versus 6 versus 2? Are the marketers more effective and I'll sell more? Same with the Doc and all others...

better doctor = less driver atrofy ( ie their stats don't drop so fast)
better designer = larger developments each update

once you have sponsors to 1.5mil, then better commercial is a waste of money.

tech director is also in that boat i believe still. I used to think that a better tech dir gave better pitstops, but it's not the case.

those last 2 you can live with the cheapo ones and not be missing out

Isnt better commercial better merchandise sales?

As far as I know, right now, they don't effect it. But it would have made sense if they did.

When you talk about a better doctor for example, is that just on overall level?
Or on the stats inside that triangle diagram?

Marketer Skill currently has no effect on merch sales. Neither does your Commercial Manager, for that matter.

Triangle diagrams for staff generally don't matter either, only overall level. The exception to this that I have found is the Experience rating of Technical Directors. With them, as Experience goes up, the litres/lap values they give decrease. Staff do gain Experience (0.1 per race) over time, but it doesn't affect their levels.