Brock's unstoppable aura would be gone if he lost, clean or not. His first "loss" was at WrestleMania, but he wasn't pinned in that. His second one wasn't really a loss, it was just a failure to reclaim the WWE Championship (BattleGround). If he loses at SummerSlam, clean or not, it would be the 3rd time he falls short. That wouldn't look good for his credibility. When you're booked to squash the face of the company and the entire roster, you need to keep the momentum going, not have him fall short 3 times in a row. And here's one thing to remember, booking 101 says that whoever gets the upper hand on the go home show loses the match on that Sunday's PPV. So me, I'm counting on a Lesnar win
While that is sometimes true, it's hardly a rule set in stone. Promoters aren't completely stupid and they are aware that this is exactly what we expect.
As much as I absolutely HATE this idea, I'm leaning towards a rubber match here. Undertaker beats Lesnar, probably not cleanly at all, Lesnar disappears for a while but Undertaker doesn't. Lesnar eventually comes back for revenge and retires Undertaker.
I absolutely don't like this idea. As I've mentioned many times, I'd prefer a Lesnar win. But Undertaker likes Lesnar a LOT, and there's probably no one better to believably retire Undertaker... Lesnar then becomes not only the man to beat the streak, but to retire the Undertaker and he retains his aura.
And again, just because everyone seems to think I'm arguing this because I want it, I don't particularly like the idea. Just I've spent a LOT of time thinking about it and it seems likely to me.
Officially, I want to see Lesnar F5 the hell out of Undertaker so I can bask in the 5 star promo Heyman is going to deliver on RAW on Monday. I just don't believe it will happen.