The only weight that really matters here is the weight of the bike plus gear plus you plus your clothes (and anything else you bring). In other words, what a truck scale would record. The touring bike has a gear that is 72% of your endurance bike. This means for the same effort (not speed!) you can haul 39% more. Let's say you (including clothes, shoes and everything in your pockets) weigh 210 pounds. Say you have 3 pounds of stuff on each bike. Now, first your endurance bike:

Weight = 210+22+3 = 235 pounds

Now your touring bike: Wt = 210+30+3+20 = 263. 263/139 = 189 pounds. Yes, your touring bike will be easier by 24%. But your hill will take 39% longer so you got nothing free.

Back to FB's points - riding your touring bike is probably a good place to start. Ride it to the top. Don't sweat the time. Do it until you can make it riding one gear higher. Do that a few times. Then you will be ready for your endurance bike. You'll make it AND it will be both fun and a lot faster. You won't look back.

Ben