A little input on my part. Perhaps it will help explain my character's actions a bit. First, I have to say I honestly don't agree. Today, it's still hacking when you change your shut-down screen on your computer, even though you're not touching other people's computers. It's low-level hacking, but hacking none-the-less. So it's still "sorta" netrunning when you are covering up tracks on the net. Second, he's still lying anyway, though Spiff doesn't know it. I recall a post where he was trying to jack into a phone line outside a Wild Things club

.
On a side note, the fact that Spiff is mixing the two is a dead give-away that he doesn't care so-much about jacking in as just covering their tracks. There are pretty decent odds Preacher could manage that without jacking in, which is exactly what Spiff is saying, and all that he's really asking.
Spiff ain't askin' for a top-o-the-line netrunner. If he was on that level, do you think he'd be working for jack? Honestly, he's just trying to expand his organization's capabilities in a direction he hasn't yet gone, which he will clarify as necessary to Preacher.
Also, the reason I post this here, is 'cause I can't find a good way to put it into the in-character portion of the post.