Someone taking a standard action like check-raising the flop or 3-betting preflop two hands in a row means absolutely nothing. Maybe we can say, that they have those plays in their repertoire, so we dont want to overfold, but thats about it. This is the whole reason, why I strongly recommend using a tracker / HUD on sites, where they are allowed.
The tracker remember everything, a player did before, and therefore we can eventually draw reliable conclusions, that someone is being overly aggressive. Many people think, manual reads are more valuable. But its the exact opposite, since manual reads almost always suffer from severe sample size issues, which can lead to overadjusting based on faulty assumptions. Yeah they 3-bet two hands in a row, but maybe they just picked up AK and QQ, and both were standard 3-bets for value. We simply dont know.
Manual reads are only valuable, when people take non-standard actions like moving all-in preflop for way to many blinds. Then it will definitely matter to my decision, if I have seen the same player do it even just a single time before during the last orbit or two. In that case I will assume, he is someone, who wants to gamble it up, and I will not put him on a range of only aces or kings, when he ships in his 72BB (again).