Hoffman followed up an opening round 66 with a birdie-filled second round 65 to extend his clubhouse advantage, with world No 3 Henrik Stenson part of a three-way tie for second three strokes back.
The overnight leader dropped a stroke at the par-four first after twice finding the bunker and then missing a 15-foot putt, but responded with six birdies from seven holes to reach the turn in 31.
After firing his tee-shot at the 15th in to thick rough and seeing his lengthy par-save putt pull up short, he posted three further gains on the back nine to move 13-under for the tournament.
Hoffmann’s halfway total of 131 was just one shot outside the tournament record set by Adam Scott last year, remarkable considering the American discovered before his opening round that his 97-year-old grandmother had passed away.
The 25-year-old plans to attend a memorial service for her in Fort Lauderdale on Saturday prior to his third round, telling Sky Sports 4: “There are times in your life when you really get hit by something and that was yesterday for me.
“It helped me appreciate life and being out here, enjoying the weather and playing golf. I am living my dream so I can’t be happier.
“I’m really not going to think about it or look at any scores. Just going to??try and hit the middle of the greens and stick to my plan.”
Stenson reeled off four successive birdies, including a monster 45-foot gain at the 17th, to complete the back nine in just 30 and move to 10-under alongside Matt Every and Farmers Insurance Open runner-up Harris English.
Beginning at the 10th, Every dropped shots with a three-putt from 40-feet at 13 and a tee-shot in to the rough at 18, but fired eight birdies ??? including five in a row on the front nine ??? in a second round 66.
American Ben Martin was four off the lead after a 67, with McIlroy another shot back alongside New Zealand’s Danny Lee – whose 64 was the lowest round of the day – and Sweden’s David Lingmerth.
McIlroy remains in contention after firing five birdies in a row on his way to breaking 70 for the first time on the PGA Tour in 2015, while Brooks Koepka believes there???s still work to be done with his game despite shooting 66 on Friday.
???I haven???t hit the ball good at all the past two days,??? Koepka told Sky Sports 4. ???Even today I didn???t feel like I hit it pretty well and was scoring.
???I???m struggling, losing the ball right, getting under hit and make the best of it, so hopefully I can figure this out for the weekend.”
World No 4 Adam Scott safetly progressed to the weekend despite striking six bogeys in an erratic second round 73, although last week’s WGC-Cadillac Championship runner-up J.B Holmes looks set to miss out on a low-scoring leaderboard despite sitting one-under for the week.