Well, the Poona to London stretch was pretty uninteresting, especially re. the food on the BA flight. From there on, it was amazing! Definetly plan on doing it again - and next time I will drive through your fair country!
Actually I’ve driven a fair bit in Germany, mostly on the autobahns, and although there was plenty of road repair going on, the crawls didn’t last too long - at least not long enough to dampen the fun of driving at 200 km/h+ speeds.
Or maybe that’s just me. Hereabouts, there’s only a handful of roads where you can drive at more than 100 km/h - most of our roads suck - so when you have the opportunity to floor it, the occasional crawl you peacefully egonre. YMMV.
Sadly, because of EU regulations, Germany has to put in a speed limit eventually. They told me this on a recent visit to Munich. Amazingly, Germans don’t seem too angry about this. Brits would be up in fucking arms yelling about bent bananas and paperboys 
What was quite startling was the fact that every single car on the road seemed to be a BMW or a Mercedes. Now of course these are both German brands, and many were mid-market models, so when you think about it, it’s no surprise.
But having lived in countries where those cars tend only to be sold as luxury models - with the main mid-market and cheaper cars being Japanese etc - it was quite stunning. It looked like Luxuryville.
Information about Autobahn repair/construction stretches:
To use: click on autobahn number; to enlarge a shaded map area.
Meaning of the table columns on the page that opens, from left to right:
Anschlußstelle(n): exits bracketing the repair/construction stretch and their numbers
Kilometer: beginning and end of repair/construction stretch in milepost kilometers
Länge: length of repair/construction stretch
vom-bis: scheduled beginning and end dates, dd.mm.yyyy notation. Im Bau = work has already started.
Geschw.: speed limit on the stretch under repair/construction
WvFs: if “Ja”, one or more lanes unavailable to traffic.
Art der Bauarbeiten: general description of the work carried out.
On the topic of behaviour, I would strongly advise not tailgate cars in the left lane that you would like to pass - this behaviour is considered at best loutish and at worst criminal (endangerment, coercion (up to three years in prison)).
Further information in English from one Texas Highway Man’s site.