Yeah, well... IMHO also damage, and not only speed is improved with proficiency...
For those who don't believe me, just do a simple try: restart the game and check on a bunch of enemies... Even with the best of your playing skills you're gonna have problems, just because you will be used to play with a character which has certain stats (especially on strength, agility and proficiency, for the purposes of combat)... and these stats (if you don't cheat) will be much lower than your first character's... So you'll certainly be able to notice the differences.
Regarding polearms, they do couch faster and recover faster after a hit. But it's not only faster... You surely know that there's a speed threshold which determinates when the polearm will be couched... The proficiency lowers this threshold, making your polearm couch sooner (and also with better effects).
The same way you can reload your ranged weapon (in this case, i agree that precision is the most visible effect of proficiency)
The swings of melee weapons are basically much faster and they become more and more lethal going forward with improvements.
Anyway, I think the most important skill to be improved on game is experience... not the one of the character, but the one of the player who commands it from the keyboard! I mean, you could have proficiencies at 400 and not be able to catch time to hit or take aim to enemies... Or have proficiencies at 50 and accumulated lots of fights with older characters and be an expert of the game.
This is "just" because this game is made differently from any other rpg you may find. Here you may be at level 50 and be killed with a simple arrow cast from the bow of a weaker enemy. Just try other games... you'll NEVER be killed by weaker enemies...
I love this game for many reasons... and this is the first!
Avandrel