Two or three short sentences, followed by a long one are a great way to get people reading.
You get their attention. Kid them it’s an easy read. Then hit them with a few dirty facts in the third sentence, before they know they’re cornered. Then you start it all again. Quicken the pace. And ram another juicy fact down their throat.
This - this is beautiful. The entire article is worth reading just for this. It's been quite a while since I've read copywriting advice this good - most copywriting articles IMO tend to be fluffy and generic. Maybe because they're not actually written by good copywriters. ;)