Loss of Strength With 70-80%of 1RM

Hi folks-
i have a problem to trigger my intensity ranges for optimum progress-I give you a short overview:

I switch between acc.and intens.phases-this was my idea.(4 weeks deload other phase for 4 weeks, deload etc.)

during the acc.phase i stick to a rep/set range of 36-50 and 1-2min rest working out each bodypart 3x the week (see set rep bible of Waterbury)
Reps of 6-12
The compounds are always included on one day(for benchmark controll)-on the others I mix the exercises up of course.

During the intens.phase I do 3-5 reps of 3-5 sets of 3-5min rest.with 80-95% of 1rpm.3x the week,only the compounds.

I started with my first acc.block and then the intens.block some months ago. The first rotation was suxessfull-but this was also because of some lousy methods i lost my strength-so after my first rotation i had my old strength back.(after the intens.phase)
Now i did my second acc.block-and I got stronger in my exercises-during the block!.

Today i tested my rep mark for 6-10(i stick to this count cause under 6 its too neuronal and above 10 too endurance testing orientated-read thibs articles on that.)
on all! exercises i got weaker-no i got no bad day,diet was in check,I felt really strong.

Why the hell is that-do you think I have to work perhaps in the 80-90% range for the acc.phases and in the 90-100% range for intens.phases?
I cam traininf for 7 years now-is 70% already too low for me?
I need help on this topic-please,every suggestion is welcome.
Goal is mass and strength.

Thank you
science

So are we talking about the volume of weight you can lift going down? Or your 6-10 rm going down. Because the two aren’t necessarily the same thing.

Thanx for your reply!

Hm lets see-the volume of work increased ( only a bit but yes)-so i was able to do my 36-50 rep/set-volume with more weight than the previous acc.block.
But nevertheless my 6-10rpm got weaker-are they not linked with each other? And why?

come on guys NO suggestions?

Come on guys-a little help =(

no suggestion guys?=(

Maybe you were slightly dehydrated? Maybe your form was more strict this time? Maybe the previous test was just an exceptionally good day?