Does Application Personalization affect logon times?

So I was wondering, we have some users with quite a big personalization profile, like 20-40mb. 95% of this is Firefox and Chrome personalization data. Windows Settings Groups size is mostly like 1-4mb which is quite normal.

From my point of view, Application data is not interfering with logon times because it gets synched when you launch the application. WSG gets synched at logon and logoff in our case, so the size of that is directly interfering with logon times.

Am I correct in this case? Or is our application data in some other way involved during the logon process. Because than i'll probably gonna trim some Application Groups..

Thanks,