How to apply transition with keystroke? FCP 5.1
 

I do alot of onscreen scripture refs for my church videos, and it'd be REALLY nice to not have to mouse the transitions onto the scripture overlays all the time. Is there a way to set up a key-combo to apply the fade in and fade out to a selected clip? I use transparent PNGs for the scripture overlays -- ALOT of scripture! Also the speaker's name and other info 'blurbs' that need to come up use the fade in/fade out transition...

Keycombo? Function key? Verbal command? I'm open. :-)

Make the fade your Default transition
 

then use: "shift + F10" to load the clip from the viewer into the target track in the timeline. That'll take care of one side, you then can click the end of each clip in the timeline and press: "command + T to apply the default transition again to the end.

To make any transition your default, right click it in the bin and select: "default transition".

If the clips are similar in length (which I doubt) you could set keyframes in the opacity and then "paste attributes", but a 30 frame dissolve on a 1 minute clip will become a 3 frame on a 10 second clip. So that won't work, since unchecking "Scale Attributes Time" would offset the keyframes.

Try plan A.

Setting favourite transitions and filters are covered in Vol. 3, part 2 of the FCP User Manual, pages 333-336 (in Preview pages would be 1118-1121).