The really hilariously ill-conceived part of the Twitter rate limiting thing is that comments and retweets are the same kind of entity as tweets in the back-end database, they're just "parented" to whatever tweet they're commenting on or retweeting, and the rate limit they've placed on the API simply counts how many of those entities you've requested without checking a. whether they're the children of another entity or not, nor b. whether you've already seen that particular entity today.
Thus, the limit isn't really "600 tweets". A tweet, each comment on that tweet, and each retweet of that tweet all count against the limit as you view them. For example, if a quote-retweet crosses your dashboard, the quote-retweet itself and the little preview of what it's responding to that appears above it each count separately against the limit. Click into that quote-retweet to read the comments? They both get counted against your limit a second time, as does each individual comment you read – and heaven help you if any of those comments were themselves commented upon!
The upshot is that if your account isn't verified, using Twitter in the manner that its own monetisation model assumes – and, indeed demands – it will be used can easily exhaust your entire daily allocation of tweet views in as little as a couple dozen engagements.
