In R/B, you could, theoretically, trap yourself if you deleted a move at the wrong time. --- Chuck Finley is Forever! People that agree: 5. I believe in Jesus Christ as my Lord and Savior and am 100% proud of it. Yeah, it's hot, but it's a dry heat.
I think I got stuck in one of the Gen 4 games The man on that secluded island that wanted to trade a Finneon for a Magikarp... Finneon was my only mon with me that could learn Surf --- http://25.media.tumblr.com/tumblr_mdtqd6EJTY1qlpahho1_500.jpg My husbando <3
That logic is no longer applicable/necessary though, because we have infinite storage space, so you have no reason not to keep HM's in your inventory at all times, which allows for them to be retaught any time if you actually get yourself stuck.
So, just forcing you to keep the item in your inventory is a better solution these days. --- PSN: TheUndying84
I guess that's why we only needed like four HMs in B/W/2. I am used to always having two full HM slaves with me, but in gen 5, I was able to evenly train 6 Pokemon. I only had to switch out for an HM user a few times. --- "The most important thing is to never stop questioning." -Albert Einstein. Xbox Live: AlteraLateralus