I wouldn't recommend Universal and Disney in 2 weeks. You won't get it … I wouldn't recommend Universal and Disney in 2 weeks. You won't get it all in and it can get a bit hectic and stressy going to parks for 14 days straight. Also the parks are about 45 minutes apart with traffic and the everlasting roadworks so it's a logistical nightmare too.
My Experience is very different to yours! We did do all the parks, some like Universal and Magic Kingdom a few times each. If you apply yourself, use fastpass you can get round the parks in a day easily - half a day if there are some rides and attractions you are not interested in (Small World for example...) and you time it well using the app to check queue lengths before heading to the next thing.
Disney and the fast pass system especially means you can do all the rides you want in the morning, then you get another fastpass. If you set that for a time that gives you enough time on the way then you are laughing. You just need to book FP a few days in advance to get the early slots.
So we definitely managed to do it all and have a few days not doing the parks at all.
We found the parks are only about a 10 minute drive apart too, however you would have to factor in leaving and entering in that time too.
I expect the main thing here was that we were 2 adults, no kids. That will massively change the pace. Also not having to queue to meet Mickey Mouse and Elsa saves you a ton of time
Ps we got our flights with BA, cheaper than all the holiday airlines!