Gem level past 20 (with + to skills)

Sorry, I am still confused on this issue. Should I succeed in leveling a Skill Gem to its maximum level (20), would it profit in any way from being socketed in an item which grants +skill levels to that gem? I cannot find information on level 22 gems on the wiki, so am unsure if this is even supported by the engine. (I know it was in D2.) Can anyone give me a short clarification please? I am attempting to plan gear and gem trading. Thank you.

Yes, they continue to scale higher, up to level 23 I believe.

Edit:

"

Skill and support gems now have balance values that go higher than level 20, so that if you get a gem at max level (which is still 20) but have items that increase the gem level, then the skill is more powerful.

This is from the .10.0 patch notes http://www.pathofexile.com/forum/view-thread/70479

Thank you for that very clear reply. I am an idiot for having missed that.
Should I ever be fortunate enough to be in a position to obtain values on gems past 20, I will update the wiki.