A) Fuzzy match repair

Project Settings - Language Pairs - All Language Pairs - Match Repair - Turn everything off

B) It has occurred to them, you just have to familiarize yourself with the software features. It's called LookAhead.

Options - Automation - Enable LookAhead

Disabling fuzzy match repair might also help a little with the lookup speed.

Thanks for these suggestions.

I was told by Jerzy in that other thread (community.sdl.com/.../sdl-2019-auto-substitution-of-numbers-not-working) that LookAhead is not a good idea (doesn't work well?) and should only be used on a less powerful machine. 

But you recommend it so I'll try it along with the other things.

Christopher Scully said:

But you recommend it so I'll try it along with the other things.

No she didn't. She just told you what the option was.

Lookahead is great when working interactively with machine translation or other remote resurces as it reduces the wait while Studio talks to the server.  If you're not doing this then turn it off.

Paul Filkin said:

Lookahead is great when working interactively with machine translation or other remote resurces as it reduces the wait while Studio talks to the server.  If you're not doing this then turn it off.

And, as with anything else, read the Help to understand what it does and to see if it's what you want/need.

https://docs.sdl.com/LiveContent/content/en-US/SDL%20Trados%20Studio%20Help-v4/GUID-A57EB808-DEDE-4CC7-94D3-10EDC09BB7F8

This part is particularly important:

https://docs.sdl.com/LiveContent/content/en-US/SDL%20Trados%20Studio%20Help-v4/GUID-A57EB808-DEDE-4CC7-94D3-10EDC09BB7F8#docid=GUID-91D2ED26-9870-421D-980B-CD1D708D7728&filename=GUID-91D2ED26-9870-421D-980B-CD1D708D7728.xml&query=&scope=&tid=&resource=&inner_id=&addHistory=true&toc=false&eventType=lcContent.loadDocGUID-91D2ED26-9870-421D-980B-CD1D708D7728

Thanks. So if I understand you, the results when using Lookahead in a normal session will not be as good as if you don't use it??

That begs the question: So why would lookahead functionality not be routine then? I.e. while the user is cogitating on segment S the machine/app has nothing to do and might as well be looking ahead at the next segments, doing fuzzy matching, and getting ready to "serve up" the next results when the user moves on to S+1, S+2, etc... ?

Thanks Nora, I'll take a look at those links...

The reason for suggesting you disable this is because you have already complained about the way it works.  It does have flaws that need to be addressed and a quick search in here will show you that.  The way you describe it is exactly the way it works today if you enable it, but with a reasonable machine and no need to reduce slow look up times caused by poor connectivity for example there seems less value in using it.

Thanks. In my question I talked about phenomena A and B: B is the slowness I am finding with fuzzy matching with segments consisting of 30 or more words.  I should mention that I tend to translate with a colossal TM, built up over years, so maybe that is a factor here. 

If I turn off the "Match Repair" stuff maybe it'll become less sluggish but at the moment working *without* lookahead just on a normal translation job is painful in the extreme:  I am talking of waits of up to a minute. Insane.

Thanks. In my question I talked about phenomena A and B: B is the slowness I am finding with fuzzy matching with segments consisting of 30 or more words.  I should mention that I tend to translate with a colossal TM, built up over years, so maybe that is a factor here. 

If I turn off the "Match Repair" stuff maybe it'll become less sluggish but at the moment working *without* lookahead just on a normal translation job is painful in the extreme:  I am talking of waits of up to a minute. Insane.

Christopher Scully said:

I should mention that I tend to translate with a colossal TM

What is a colossal TM?

Christopher Scully said:

I am talking of waits of up to a minute.

Clearly there is something wrong here.  But it would be good to know what size your resources are.  Most performance issues in Studio are related to influences such as these:

https://gateway.rws.com/csm?id=kb_article_view&sysparm_article=KB0032531

Thanks.  I'll also follow this up.