It's been a while since you mentioned the 4 minute mash
Any mash takes longer than extract. Steep your grain as it heats, remove it at 155, add some extract at 60 and the rest at 15 or 10. Shake out grains and rinse bag. Never pause for mash or sparge.
Extract is faster than mashing because it's been mashed.
Since you didn't figure it out and are sure that extract is faster than all grain let me lay it out for you. Notice that I said that I can do an all grain as fast as extract with steeping grains if you follow the instructions. The instructions will have you steeping the grain for 30 minutes. Fine, I mash for 30 minutes so that comes out the same. I mill the grains while the water is heating so that doesn't take extra time. So far the mash and extract are taking the same time. Now add your extract. That takes time too but it is done while doing the hour long boil. I've learned that the hour long boil is to isomerize the hop oils for bittering but that 90% of that happens in the first 30 minutes. Why spend more time boiling? Because it reduces the water and drives off DMS! OK, I start with less water so I don't have so much to boil off and.....I haven't found DMS even with the short boil. YMMV Chilling does take longer because I have to chill the full volume of wort instead of just the partial that you would have with an extract batch but not a half hour longer.
Note: If you want to try the short mash period, you must have the grains milled very fine. If not, you will not get complete conversion of starch which may leave you with a starch haze in your beer and for sure will reduce the efficiency.