And yet you would clear them on a regular bike? Is that because the regular bike is half the weight, so needs less momentum to jump, or you can crank your regular bike faster without hitting treacle?
Like I've already said, it depends on the jump (and the gradient between them).
Take my local BMX track for instance. Start hill> tripple (single roller to step-up double) > double > bigger double - flat inbetween and usually into a headwind. On my BMX or 4X bike the line is an all our sprint at aguess hitting all transitions somewhere between 25-30mph. Just not do-able on a 48lb Emtb restricted to 14.5mph assist.
another example. Local dirt jumps, one line is a flat pedal at about 20-22mph ish into a roller/speed jump then a shallow bowl into the line of tight steep tombstone doubles. holding momentum into the speed jump then getting sufficient pump after it and getting through the entire line just isn't anywhere near as easily do-able as on a bmx or DJ bike. Not impossible but the effort you have to put into pumping and lifting the bike is horrendous.
and a third example. Trail centre RED descents like you find at places like Glentress, Ae Forest etc., They're on the whole flat AF bermed hardpack sprint fests but have lots of jumps, a lot of those jumps are best hit at above 17mph... I can't actually be arsed finishing this example.. .hopefully you'll get it by now.
I think the feeling of hitting treacle is a psychological issue, have a regular bike in the same gear as the ebike at 15mph, it will feel the same, at least for shimano and browse. I agree the bosch system is flawed.
I ride my Emtb switched OFF a lot. it's not psycological. it weighs 17-25lb more than my other non-Emtbs. it's 13lb heavier than my DH bikes FFS. Above 14.5mph restricted it accelerates like a towing dead pig behind you on the flat. "Accelerates" being the key word here. holding 17mph on the flat isn't difficult. Sprinting to 25-30 is.
I didn't mention "treacle" once! The "treacle" feeling is IMO a phenomenon caused by weak riders and super draggy tyres. (with the Shimano motor anyway). I run fast rolling tyres on my Emtb and ride normal bikes a lot so i'm not weak.
Gearing isn't the issue either. My Cadence range is huge and I generally don't change gear at all jumping, descenting trail centres or at the BMX track on a non Ebike
Don't get me wrong. My Emtb is awesome at almost all mtb riding but it's certainly not without it's flaws. And I wouldn't ever pretend otherwise.
Disclaimer: I haven't ever ridden a Bosch motor so have no idea what motor drag feels like