What to do if you're stuck in a bootloop and need to soft reset so you can get into recovery:
To get into recovery:
Long press power + volume down reboots the phone.
Wait for it to vibrate and immediately switch to volume up + keep holding power + home key.
Once you see 'Recovery Booting' (in dark blue, top left) release the keys.
To get into download mode:
Wait for it to vibrate and immediately press the home key + keep holding power + keep holding volume down.
Timing is a little critical but at least I don't have to pull the battery every time I get stuck testing something and want to get into recovery to fix it.