And Williams speaks from experience.
The 34-year-old openside made his first-class debut 13 years ago and has since seen domestic rugby in this country take on a number of guises.
First there was the Heineken League starting with 12 Welsh clubs, including his own beloved Pontypridd, then the WRU National League followed by the Welsh-Scottish League.
Then came the first premise for a Celtic League which in turn progressed into today's higher-profile Magners League.
Even the current competition has undergone radical changes, with the original 12 entrants being reduced by two with the demise of the Border Reivers and the Celtic Warriors. Add in this year's introduction of a brand new play-off system featuring the top four sides and it's clear to see why the Magners League is suddenly so high on everyone's agenda.
And while Williams admits that the Welsh derbies of old will always hold a place in his heart, the Cardiff Blues star has no doubt that the Magners League has been a major blessing for the Welsh national team as a whole.
"The Magners League is a great competition and it's getting stronger year-in year-out," said Williams.
"So much has changed since my debut with Ponty in 1995. Gone are the days of going up to Ebbw Vale and Pontypool and you obviously miss those games but you're now playing at Murrayfield or out in Munster.
"Wales have got a lot stronger as a national side, so too Ireland, since the Magners League has really kicked in.
"The play-offs are also a great concept. They'll help not only the club sides but also the national side because most of the players will be playing competitively right up until before they go on tour in June."
Williams isn't wrong when he highlights the benefits of a hard-fought domestic league when it comes to producing winning rugby on the international front.
A better standard of regular regional rugby generally leads to battle-hardened players who know they have to perform every time they step out on to the field of play rather than picking and choosing when they produce the goods.
Williams knows form isn't something you can switch on and off whenever the occasion suits and he recognises the role the Magners League can play in getting the nation's elite ready for the rigours of Test rugby.
The triple British & Irish Lions tourist admits that previous competitions may not have always provided the intensity required to narrow the gap between domestic and international rugby but he insists all that has changed with the current nature of the Magners League and the success of its sides in continental competition.
"Initially, some sides may have been more focussed on Europe and maybe not put their strongest side out but that's gone now," added Williams.
"Clubs are signing the likes of Jean de Villiers and Xavier Rush - overseas guys who are having a huge influence.
"The old Welsh-Scottish league was a great competition but the Magners League is getting more and more exposure, especially with the Irish teams being so successful and with Glasgow flying at the moment.
"In Europe, we've shown that we're rivalling the perceived stronger competitions in the Top 14 and the Guinness Premiership.
"With the invention of the play offs and the Grand Final, it's a huge competition with top sides playing week-in week-out."
Overall, it's been a mixed season so far for the four Welsh regions on the Magners League front.
While the Ospreys are flying high in second place in the standings, the Dragons, Scarlets and Williams' Blues all sit outside the prized play-off places.
Under the format of previous years, when the Magners League Champions were decided by whoever finished top at the end of the regular season, Williams' chances of adding to his trophy collection would have all but been extinguished by now.
The Blues currently sit in eighth position, some 12 points off leaders Glasgow having played a game more than the in-form Scots.
But the addition of a Magners League Semi-Final and Grand Final to crown the end-of-season champions means Williams and co still have plenty to play for throughout the remainder of a highly-competitive campaign.
"Everyone's saying that the Blues want to be one of the top three Welsh teams to qualify for Europe next season but it's such a tight league that we need to push for more than that and try and finish in the top four.
"Points can be picked up very quickly and there's not that much of a gap.
"It's been quite a disappointing first half of the season but we can still go from strength to strength and hopefully be there right at the end. We're behind the eight ball at the moment but I'm sure there's enough quality to get us out of there.
"If you look at guys like Gethin Jenkins and Jamie Roberts, world-class players, there are a lot of them in our changing room. If we can keep everybody fit between now and the knockout stages, hopefully we can be in there alive and kicking at the end."
Guinness PRO12
Suite 208, Alexandra House,
The Sweepstakes
Ballsbridge, Dublin 4, Ireland