The issue (illustrated within!)
An essay, an article, a blog post is sequential. I start writing, and if I'm lucky you start reading, at the beginning and follow through to the end, or to the point at which I loose your interest.
But there are so many asides that I want to add - commentaries on the background to what I have said. And those asides have often lead me off into bracketed
(parenthesized) elements which go off at a tangent. By doing so, they leave my text harder to follow.
(I could say they may help in search engine placement - but here I go again with another tangent - in this case as an example).

Journeys are sequential too. If you've ever driven from (say) Wiltshire to Glasgow as I'll be doing just after next weekend, but then taken a side trip to somewhere just off the road, you'll realise how expensive in time that short diversion can be.
Or if you have seen something roadside and stopped to take pictures as I did on my way back from Devizes on Sunday - and in doing so provide another example of a tangent to the article with an excess example.
On a web page, interesting links can be the worst of tangents - if I tell you that the picture on the right is one I took at
Devizes Court House, I am likely to loose you and never have you come back -
rather like the much despised "Go to" statement in a program - and there's a tangential metaphor!.
The training solution
It's very easy to go off on a tangent during a training course too. And that's why I always start by checking that with my delegates what we want to achieve.
• Targets are defined, so that possible tangents can be evaluated to see if they lead us in the right direction
• Questions / Topics which would require lengthy rambles when raised, but will be answered later on the course, are added to a list on the board. That way, they're not forgotten but neither do they disturb the flow
• Specific issues that relate to just one or two delegates are put aside until we have an exercise running - with group sizes limited to 8, the tutor then has the time to answer topics that are a tangent to most delegates, but critical topics for a few
• Before we start in the mornings, after course in the late afternoon, and over lunch ... we can (and do) enjoy some lovely discussions that are off topic (and, yes, that's sometimes COMPLETELY off topic!)
So - at the end of the course, I can ask:
• Did we cover everything
I set out at the start?
Check - YES
• Did we cover each extra topic that
you had me add?
Check - YES
• Good Course?
Check - YES
A listing of scheduled public courses is available
[here]. That link's not a tangent - I would like you to go there, select your subject, and book a course, please!
(written 2010-05-04)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
G905 - Well House Consultants - Blogging and Blog Administration [1] First Jottings - (2004-08-05)
[6] Blog v Forum - (2004-08-07)
[18] Wanted: More hours in the day - (2004-08-18)
[141] Too technical? - (2004-12-05)
[145] A comment on comments - (2004-12-09)
[177] Blogs come of age - (2005-01-14)
[185] Who am I? - (2005-01-21)
[204] The confidence to allow public comments - (2005-02-06)
[231] Feedback as lifeblood - (2005-02-28)
[245] I'm not blogging it - (2005-03-14)
[359] Chicken soup without the religion - (2005-06-26)
[390] Moderating wiki, blog, and forum contributions - (2005-07-26)
[405] Horse's Mouth is a year old - (2005-08-07)
[410] Reading a news or blog feed (RSS) in your PHP page - (2005-08-12)
[425] Caching an XML feed - (2005-08-26)
[508] Comment, please! - (2005-11-28)
[671] Both ends of the animal - (2006-04-05)
[876] Making pages clearer - easy Disability Discrimination Act Compliance - (2006-09-23)
[1000] One Thousand Posts and still going strong - (2006-12-18)
[1077] In answer to 'am I glad I started a blog' ... - (2007-02-12)
[1203] A Fresh horse - (2007-05-24)
[1978] From spam to mod_alias - finding resources - (2009-01-05)
[2000] 2000th article - Remember the background and basics - (2009-01-18)
[2192] Copy writing - allowing for the cut - (2009-05-21)
[2449] Four aspects - Chamber, Transport, Courses and Hotel - (2009-10-11)
[2517] Blogging accuracy - open invitation for any corrections - (2009-11-29)
[2564] Microblogging services - Plurk, Twitter, Jaiku and more - (2010-01-05)
[2823] Where have all the bloggers gone? - (2010-06-24)
[3016] The legal considerations of your web presence - revisited - (2010-10-26)
[3163] Twitter - the special use of @ # and http: in tweets - (2011-02-09)
[3186] How to add a customised twitter feed to your site - (2011-02-27)
[3208] Links for social media, microblogs and business networking - (2011-03-20)
[3514] Microblogging - what I should have tweeted in the last 48 hours - (2011-11-10)
[3759] The five oldest blogs and the horses mouth - (2012-06-09)
[4000] 9 years, and 4000 articles on - (2013-02-09)
[4121] Has your Twitter feed stopped working? Switching to their new API - (2013-06-23)
[4292] The Horse is back! - (2014-09-15)
[4568] Moderation - and the tendency to over-moderate - (2015-11-02)
[4714] The technical article feed continues - personal updates more proactive on Facebook now! - (2016-10-30)
Some other Articles
Books in the store in the USA - still a portent of the UK market to come?At Arlington and the PentagonYou do not just fly - that is just part of the journeyVoting day - UK General ElectionGoing off at a tangent, for a rambleViews of WessexDelegate Question - defining MySQL table relationships as you create the tablesMonitoring the success and traffic of your web siteContainment, Associative Objects, Inheritance, packages and modulesModel - View - Controller demo, Sqlite - Python 3 - Qt4