Is it a good idea?

I got completely rid of my first UFO today. The dress pieces, the toile made in the same fabric including the zip from the toile all gone - at least, the pieces are in the scrap bag ready to take to class. There is also a leftover piece of the fabric but to be honest, I can't stand it anymore. Too much hassle in the process of working through this garment.

I am a Scot, though! The zip was perfectly fine, I thought, and quite expensive to get the colour I wanted. So I decided to unpick it. It's a concealed/invisible zip. I sewed it in over interfacing to give some strength and some structure to the rather floppy fabric. I remember (now! after the unpicking!) that I had some problems sewing this zip because the teeth seemed slightly too big for my concealed zipper foot, which normally works very well. In fact, the zip that I threw out was cut apart as I couldn't get it out of the toile - that was a while ago, so I think I can be forgiven for forgetting. Rory put that zip in using a standard foot or a ordinary zipper foot when I couldn't get it to go in at all using my concealed zipper foot. Back to this one - because the teeth were a little sticky in the zipper foot, some of the stitches were VERY tiny. I wasn't too worried as that was the 'final' version of the dress.

So the problem was that I had great difficulty getting this zip out. In fact, now remembering the issues with sewing it in (it's a decent quality zip) maybe I should have jettisoned it too, especially given that I have jettisoned the matching fabric! Why the problems getting it out? First and foremost, the tiny stitches in certain areas. Secondly, my thread matched TOO well! I couldn't see the stitches even using my magnifying light. Fortunately in places I could see the tiny stitches showing against the white of the interfacing. The fabric tore in a few places. I was careful to avoid stretching or cutting the zipper tape.

Zip out. Thread ends still there.

You can see how closely the thread matches zip. This is very magnified.
At the left of the photo, see how the stitches nestle right against the zipper teeth
The stitching along the middle of the tape is to secure and I use as basting

Showing stitches nestling against zipper teeth

So my question to myself - and you! As this is a concealed zip where the stitching doesn't show - would I have been better using a less well matching thread to guard against the need to unpick? What do you think? David feels that would be a rather negative approach, foreseeing failure rather than success and advocates using matching thread - the thread that matches the garment if there is a slight mismatch between the garment and the zip as he believes in cutting down the variables. I see his point - and I do baste etc in advance of the final stitching.

Also - any suggestions for sewing in a zip that my concealed zipper foot really doesn't like? I did slightly open the zipper teeth using an iron, which I do find helpful usually, but not in this case.

I don't normally have any problems putting in invisible zippers. I definitely think it was the tooth size in this particular zipper - in fact, in this particular colour. Though, I wonder about the thread too. Could it have been a little on the thick side? However, I use Gutermann threads which are generally good though I did have one large reel of black that gave off fluff while sewing to a huge extent.

My camera battery went flat and the photos I thought I had taken didn't register on the sd card! I din't realise that could happen - and I didn't get any warning, so hopefully it is that and not something more serious. I've took a couple on my phone but had to wait until other tasks were done before posting. I cooked today with harissa paste, which I've never used before. Moroccan turkey kebabs - for tomorrow and freezer  and Mediterranean fish cakes for the freezer. Both Slimming World recipes.