Hmm, so when I study, how would I test out the things Ive learned and how would I know if I'm improving if ratings are not accurate?
If your rating is increasing here, you are likely improving some aspect of your play. Ratings are really only "accurate" within a pool of players.
You can get inaccuracies in regional players OTB, that play relatively the same pool of people all the time. They then go to a different area and have worse/better results than their rating would indicate, without any real change in chess knowledge/strength.
Also, look to see if you continue to make the same types of mistakes; if you are, you probably aren't improving much
Jeremy Silman says the ratings at chess.com are 200-300 higher than USCF OTB equivalents. I've coached high school kids and those with USCF regular ratings of 1200 or more had a MUCH deeper understanding of chess than the games I see by 1200 players here. I can't speak for the higher ratings.
So if Im at 1700, that means Im really 1400 OBT? :/
Chess.com standard ratings are good predictors of USCF ratings except at the extremes.
Blitz ratings are better predictors. One reason is that there is less of the notorious "extenuating circumstances" in blitz. Even so, it is a poor predictor.