Half Dome is a good preparatory climb/hike for Whitney, at least it was for me back in 1970, and I see for some others.
Yes, but he wasn't interested in hiking Half Dome- just taking pictures of it.
Whitney is why I will be in California, just want pics of half dome, but its not my main objective, so not willing to invest a ton of time on some 15 mile hike, just the drive plus a 3 to 4 hour hike at most.
This then depends on where you are driving to Whitney from.
Clouds Rest is over your time limit (But would be my top recommendation)
North Dome from Porcupine Creek can be done in 3-4 hours.
Both of those are convenient if you are driving down 395 from Reno or heading across 120 from the Bay Area/Sacramento.
(As is the backside view of Half Dome from Olmstead Point on 120)
Glacier Point and the Valley Floor are drivable, but both will be one to several hours out of your way by any route.
And if you are heading up from LA, Vegas, or AZ I'd skip Yosemite entirely.