But what you have done is different to the OP. That's like when I changed the headers on my CBR600F4, it creates a torque dip and I needed it remapped to remove that dip and smooth the power delivery out again. That's not the same thing here.
You've made an actual modification on the car and making a modification then throws more variables into the pot which you should get remapped if you want the benefit OR you caused a problem by that change. My SRT8 is an NA engine which was remapped and got around 5bhp more which isn't even worth it and even could come down to dyno fluctuation... BUT then I amended the intake at great cost that sucks in 30% plus more air, upped the fuel to 99ron VPower, replaced all the spark plugs, cleaned all the PVC recycle circuit and installed a catch can so the air is 100% pure which then messes with everything.These changes can result in power gains and is known.
So had a custom remap on this lot and it's gone from 421bhp to 451bhp (6.8% and that was with one of the best tuners in the game for Jeep in the states)... in the grand scheme of things can barely feel it. BUT, the throttle response and gear changes have all been reprogrammed and this is where it "feels" more responsive, not because of more power. Now, if I'd gona cams, headers, full exhaust and decat, yes you would have to remap as you'd screw everythiong up PLUS you'd be missing out on a LOT of extra power because you're changing complete internals.
However, the OP wasn't doing engine mods, it was simply a remap. The best he can expect is a slight smoothing on his power delivery and you'd be lucky to get anywhere near 10% imho. I'd say 2-5% at absolute best on an NA engine with no mods. However it may change his throttle response but I stand by my statement, taking a STANDARD N/A car and remapping will not make any difference to performance that you'll notice. For the cost v's benefit? nahhh. There might be the odd car that responds better or was detuned from factory but unless you know this I personally wouldn't bother.
BTW, glad your tune worked out, nice feeling when it does! What car was it?