Let's look at the numbers.....

Eejit raised to 345 and got a call. That is 690. The SB (50) and BB (100) fold. Total pot is 840. Flop hits. Eejit bet's 700 giving the calling odds of 700 into 1540 which is 2.1 to 1. Flush draw requires 3.1 to 1 to make the call. Now, given that the player has the pocket pair, you can drop that to a bit less than 3.1 to 1, if you think you are ahead and it's now a redraw. Given that we know that the villain is against a huge hand there, they are more looking for better than 3.1 to 1 to call.

Now if eejit bets 200 on the turn the pot is no 1040 and the villain has more than the odds to call. Then I push on the turn for 500 into a pot of 1240. Giving 2.5 to 1 for the river card and a hint of weakness. This makes it easier to make the call.