IPhone 6 Wifi AC Speed

You say that sometimes you "forget" to sync. Are you utilizing Wi-Fi syncing? The sync activates whenever you're on the same network and your device is plugged in. This might reduce the number of instances that you need to download a copy from your iPhone.

I realize this is a stop gap. I feel your pain. Like you, I've put a lot of effort into understanding why the leading podcast catcher can't seem to make podcasting on the iOS "just work". In the end I needed a bit of self inflicted tough-love and just admitted that this was one are that Apple fell short and that they weren't going to remedy anytime soon. They're putting their resources where the revenue streams are.

My situation forced me to change my workflow. I've been waiting for the promise an untethered world, and jumped into iCloud full steam. I use iTunes Match for my music, iCloud for my backups and no longer sync to iTunes on my computer. Of course, this means that there is no way to subscribe to podcasts on my iPhone without using a third party app.

After trying several podcast apps, I've come to like both Downcaster and Instacast. I've imported my feeds from my mac, I can subscribe to new ones on the iPhone, and I can sync to my other devices through iCloud. What I can't do is sync back to the mac. But I'm ok with that now. By using a full featured app on the iPhone, I've come to really like the experience. Given the choice today, I'd continue my new habit of listening to podcasts on my phone even while I'm working on my mac. I don't ever need iTunes open and the overall listening experience is much better.

iPhone 4S has a smaller antenna and slower processor (A5 vs. A5X) than iPad 3rd generation. More importantly, the iPhone 4S wi-fi is (802.11 b/g/n) 2.4 GHz only, while the third generation iPad has two channels — 802.11a/b/g/n Wi-Fi (802.11n 2.4GHz and 5GHz.)

I don't think the iPad uses both channels at once, but I think if the second channel is more clear or faster to your router, it would not be surprising the iPad gets faster speeds over Wi-Fi. I think a faster processor alone would allow for faster Wi-Fi speeds.

Similarly, the faster CPUs in MacBooks and iMacs would allow for faster Wi-Fi speeds, even if the networking architecture is the same. (I suspect it isn't, and that there are larger antennas in Macs than iPads, which is another factor…)